I don't know where to go from here.
Answer choices are:
a) $(7, \pi/3 + 2n\pi)$ or $(-7, \pi/3 + 2n\pi)$
b) $(7, \pi/3 + 2n\pi)$ or $(-7, \pi/3 + (2n + 1)\,\pi)$
c) $(7, \pi/3 + (2n + 1)\,\pi)$ or $(-7, \pi/3 + 2n\pi)$
d) $(7, \pi/3 + n\pi)$ or $(-7, \pi/3 + n\pi)$
Hint: Adding a multiple of $2\pi$ to the angle does not change the point. However, adding $\pi$ changes a point to its negative (the opposite to the origin). Replacing the "distance" to the origin with its negative also changes a point to its negative.
Therefore, for a given point in polar coordinates, you get the same point if you:
(1) add a multiple of $2\pi$ to the angle (which does no change), and/or
(2) add $\pi$ to the angle and reverse the sign of the "distance" from the origin (which takes the negative of the point twice, and results in no change).
Be careful, as adding a multiple of $2\pi$ to the angle and reversing the sign of the distance from the origin does not give the same point. Therefore, a) is not the correct choice. My action (2) does not add a multiple of $\pi$, just $\pi$ itself.
Can you continue from here?