Directions: In the sentence given below, one/some parts have errors and others are correct. Find out which part has an error and mark it as your answer. If there is no error mark 'No error' as your answer.

The number of key workers and members of their families who are testing positive for Covid-19 have/ (A) overtaken the number of sick people testing positive in hospitals. The number of key workers and family members testing positive reflect/ (B) a major ramping up in testing for that cohort but experts say/ (C) that it also emphasizes where the recent new cases are occurring./ (D)