This is a useless question to ask about portals, with no practical application. A better riddle is would using it to do this to yourself make you gay?:

The rope is taut because of the equal amount of force from both portals, and if you take that in mind then yes, an infinite amount of force is exerted on both sides, making it straight.

And I don't even know why you brought gravity into this, because if you're going to examine the gravitaional force on the rope and claim it's not making it straight then you may aswell talk about how the bump of the knot is stopping it from being straight, which is all completely invalid anyway because that was not the point in the question. The question is not asking if it is PERFECTLY straight, because nothing is perfectly straight, its just asking if it is going in a straight line rather than going in a circle.

White holes aren't weaker than black holes : ). And they expel instead of suck. That is why they are known as white- because you can see the light that is ejected from them. It is actually theoretically impossible to pass into a white hole.

Assuming this is an accurate representation, and the rope is in fact horizontal/being affected by gravity? Neither, both are impossible. This is because, in order to make a rope taut (as long as downward force is being exerted on the center), and by taut I mean perfectly taut, an infinite amount of force must be applied to each side of the rope. The F exerted by gravitational effect on the middle of the rope/not will make a slight dip in the path of the rope.

Thus, neither a true circle or line is created, considering both shapes are 2D Planar, whereas the depicted rope is truly 3D.

Tcos(theta)=mg/2
T=(mg/2)/cos(theta) where theta= the angle each side of the rope forms, measured from the line perpendicular to the midpoint of the rope.

As T (tension) increases, theta approaches 90 degrees. The perfectly straight rope would have a theta of 90 degrees, causing a division by 0 because cos(90)=0. The only way to mathematically counteract the division of 0 in this cause would have to be having T= infinity.

Now, there is no physical type of "portal" known that could exert an infinite amount of force on the rope in this way. While the forces are sure equal, that has no bearing on their magnitude, and whether that magnitude happens to be infinite.

The bump has nothing really to do with it, and that would certainly be ridiculous to bring into question, but I feel as if as long as we are going to be talking about this ridonculous hypothetical scenario, we might as well bring in as much physics as we possibly can : ).

I see what you're saying, but you're taking it too literal, you're proving that the rope could never be perfectly straight in this scenario, but the question here isn't asking if it's perfectly straight, it's asking whether it goes in a continuous line or a circle. In which case as long as there is at least a slight equal force on both sides, then yes it goes in a continuous line.

As for this:
"Now, there is no physical type of "portal" known that could exert an infinite amount of force on the rope in this way."

Is there ANY physical portal even known to man, not taking into account different black hole theories? If there is I would be genuinly interested in reading about it.

well in my predictions is see that it is 2 white holes (weaker than black holes) and the rope is being sucked by 2 equal forces but prevented from going in either 1 because its tied together and the knot only gets tighter so the rope cant go anywhere unless it breaks

The rope is taut because of the equal amount of force from both portals, and if you take that in mind then yes, an infinite amount of force is exerted on both sides, making it straight.

And I don't even know why you brought gravity into this, because if you're going to examine the gravitaional force on the rope and claim it's not making it straight then you may aswell talk about how the bump of the knot is stopping it from being straight, which is all completely invalid anyway because that was not the point in the question. The question is not asking if it is PERFECTLY straight, because nothing is perfectly straight, its just asking if it is going in a straight line rather than going in a circle.

So good day to you good sir!

Thus, neither a true circle or line is created, considering both shapes are 2D Planar, whereas the depicted rope is truly 3D.

The tension equation is: 2Tcos(theta)=mg

So...

Tcos(theta)=mg/2

T=(mg/2)/cos(theta) where theta= the angle each side of the rope forms, measured from the line perpendicular to the midpoint of the rope.

As T (tension) increases, theta approaches 90 degrees. The perfectly straight rope would have a theta of 90 degrees, causing a division by 0 because cos(90)=0. The only way to mathematically counteract the division of 0 in this cause would have to be having T= infinity.

Now, there is no physical type of "portal" known that could exert an infinite amount of force on the rope in this way. While the forces are sure equal, that has no bearing on their magnitude, and whether that magnitude happens to be infinite.

The bump has nothing really to do with it, and that would certainly be ridiculous to bring into question, but I feel as if as long as we are going to be talking about this ridonculous hypothetical scenario, we might as well bring in as much physics as we possibly can : ).

As for this:

"Now, there is no physical type of "portal" known that could exert an infinite amount of force on the rope in this way."

Is there ANY physical portal even known to man, not taking into account different black hole theories? If there is I would be genuinly interested in reading about it.

why? simply because of the knot

White holes, black holes, naked singularities, worm holes, etc etc. Why discount them? : P.

And I think taking it as literally as possible is the most entertaining way to assess it for me : ). Thus I will continue to do so!

or you can put one portol in another.

There is no single point anywhere from which all points along that line are even roughly equally distant, which means it can't be a circle.