Which of the following words is spelled CORRECTLY?

Acquaintance is correct because it breaks down like this: ac–quaint–ance. (-ance, not -ence)
Maintainence is incorrect because it breaks down like this: main–ten–ence.
Differance is incorrect because it breaks down like this: dif–fer–ence (remember that the adjective form is different).
Significence is incorrect because it breaks down like this: sig–nif–i–cance (remember that the adjective form is significant).