The integer x is divisible by both 10 and 15

The integer x is divisible by both 10 and 15. Which of the following must be an integer?

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 #61961