Respuesta :

[tex]\frac{7!}{5!2!} = \frac{7 * 6 * 5 * 4 * 3 * 2 * 1}{5 * 4 * 3 * 2 * 1 * 2 * 1} = \frac{7 * 6}{2 * 1} = \frac{42}{2} = 21[/tex]

The answer is B.

The correct answer is B. 21