Being fluent in Spanish, I can tell you the answer is a. The option b is plural... You'd only choose it if they were talking about more than one puppy. But SINCE you're talking about a singular baby, the answer is a.
To drive a tractor, since he went to his grandfathers to harvest sugar cane
1.pasa
2. Pasea
3.corta
4.sacude
5. Descansa
