In the following question, some parts of the sentences have errors and some are correct . Find out which part of a sentence has an error. If a sentence is free error, your answer is (d).
`("Part of the research programme")`/a `("involved interviewing teenagers")`/b `("in inner city areas")`/c `("No error")`/d

Answer

2

Explanation

It is a general rule/provision. Hence, Present Simple i.e., involves interviewing is the right usage.