Her mother does not approve of (1)/ her to go to the party (2)/ without dressing formally. (3)/ No error (4)

Options

A. 1 Her mother does not approve of
B. 2 her to go to the party
C. 3 without dressing formally.
D. 4 No Error

Answer

2

Explanation

going will replace to go because
Verbs followed by a Prep. Are followed by a Gerund.
Look at the examples given below:

Hence, her going to the party is the right usage.