The preposition that Best collacates with 'ignorant 'is: a, form
b, to
c, of
d, with ​

Form.

Explanation:

If you really think about, it cannot be of because it wouldn't really make sence with what you are thinking, to doesn't really make sence either, with neither makes sence. So the best choice would be form because it a form/ expression.

a

explanation:

the writer needs to avoid using abbreviations and check spelling before sharing.