Which sentence uses both grammar structures correctly?

A. Let’s practise speaking English. I’m good at listening but I’m not good at speaking.

B. Let’s practise speak English. I’m good at listen but I’m not good at speak.

C. Let’s practise speaking English. I’m good at listen but I’m not good at speaking.

D. Let’s practise speak English. I’m good at listening but I’m not good at speak.