What military weapon advancement led to the end of trench warfare?

Responses
A The impenetrable barbed wire surrounding the trenches rendered troops useless.
B The use of poison gas within the trenches led to massive military trench deaths.
C The invulnerability of the tank to machine gun and rifle attack decreased the tactic.
D The development of nuclear weapons caused trench warfare to become vulnerable to aerial assault.

C. The invulnerability of the tank to machine gun and rifle attack decreased the tactic.