The heights of seven boys B1, B2, B3, B4, B5, B6 and B7 is compared. They all have different heights. B2 is taller than B1 and B6. B7 is shorter than B3 and B4 but taller than B5. B5 is taller than only three boys and B3 is the tallest.
How many boys are shorter than B4 and taller than B2?

A

2

B

1

C

4

D

3