Answer: pero (male)
Explanation: I know this because im cuban +american
B. Tololo hill observatory has the largest telescope in the Southern Hemisphere
This is how your sentences will look: (Given that they are in present tense)
Usted quiere un gato.
Mis hermanas visitan a mis padres.
If you are referring to the United States, it would be A. If you are referring to Mexico, it would be B.