What are the usable hosts on the 96.6.128.0/19 network?

What are the usable hosts on the 96.6.128.0/19 network?

A.
96.6.128.1 through 96.6.143.254

B.
96.6.128.128 through 96.6.134.254

C.
96.6.128.0 through 96.6.134.254

D.
96.6.128.1 through 96.6.159.254

Explanation: