Question

How does Mario know his pet likes his new bed?

Answer 1

I think all of the above     

Answer 2

C. 
Reasoning: A: you can make yourself comfortable anywhere
B: I doubt that the animal could sing, but even if he could that does not indicate enjoying the bed
C: Sleeps, is comfortable
D His pet waves his antennae? Antennae don't usually indicate happiness, cockroaches use them as sensors.