If p and r are integers, and p^2 = 14r, then r…

If p and r are integers, and p^2 = 14r, then r must be divisible by which of the following?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #4167