During the entrance(升学)exams, there are_____parents waiting for their children outside their test center.

A. thousand of     B. thousands of    C. thousand    D. thousands

During the entrance(升学) exams, there are ___________ parents waiting for their children outside the test center.

A. thousand of        B. thousands of        C. thousand        D. thousands

During the entrance（升学）exams, there are ________ parents waiting for their children outside their test center.

1. A.
   thousand of
2. B.
   thousands of
3. C.
   thousand
4. D.
   thousands

During the entrance（升学）exams, there are ________ parents waiting for their children outside their test center.