Your Answer is

Correct Answer is B

Explanation

Because 87 is the median of the 20 people and no one got an 87, it is judged that 10 people scored 88 or higher.

It is also known that 30% of the 20 people, that is, 6 people have a score of 90 or higher.

So it can be known that 4 people got 88 or 89 points.