The captain with the members of his team (a)/ are returning (b)/ after a fortnight. ©/ No error (d)

Answer

2

Explanation

is will replace are because -
When Subjects are joined using along with, as well as, together with, the Verb agrees with the first Subject.
Singular Subject `rarr` Singular Verb (is)
Plural Subject `rarr` Plural Verb (are)
Hence, is practising very hard is the right usage.