The answer to the first one is A
First of all, you need to know what the sentence above means.
"In general, to enter a car and unlock it, you need ___."
The options are llaves (keys), antenas (antennas), espejos (mirrors), and tanques (tanks).
So obviously, based on the context, the correct answer is going to be llaves.
Voy a la sala a escuchar música y bailar.