persist vs. insist

[Lucci]

correct sentence:
User: Yes, they would do if you didn't persist in asking questions.

Correct answer: (b) persist

Your answer was: incorrect
your sentence:
User: Yes, they would do if you didn't insist in asking questions.

why do we use persist here? .. thanks..

[Cerberus™]

To persist goes with in, to insist goes with on. There are many exceptions, but this is the most likely manner in which these words are used.