He has (1)/ a large family (2)/ to care. (3)/ No error (4)

Answer

3

Explanation

to care for/to take care of will replace to care because -
to care for/to take care of (Phr.V.) : to look after somebody
And, moreover, a Preposition is used at the end of a Phrasal Verb
Look at the examples given below:
She is the person I cannot `underset("Phr.V")underset(darr)("cope with.")`
He takes good `underset("Phr.V")underset(darr)("care of ")` goats.