Thanks to medical research (1)/ our lives have become (2)/ healthier and long. (3)/No error (4)

Options

A. 1 Thanks to medical research
B. 2 our lives have become
C. 3 healthier and long.
D. 4 No error

Answer

3

Explanation

longer will replace long because-
Double Comparatives are often used for emphasizing the importance of doing/not doing a certain activity. They describe a cause-and-effect process The format of double comparatives is as follows:
The + comparative + subject + verb + the +comparative + Subject + Verb as in -

Hence, the first task is providing/ to provide is the right usage.