D: ¿Te gusta vender los collares?
Gustar conjugated is still one word so it cannot be "gust a"
A verb ("vender") is singular so you cannot use "gustan"
A verb after gustar has to be infinitive
so the correct answer is ¿Te gusta vender los collares?
Home to nearly 7,000 different species and 3.5 percent of the total aquatic life on Earth.
Comiamos la comida, the other just dont make sense in that tense
Answer: había bebido
Cuando llegué, Marcela ya se había bebido cuatro vasos de leche.
When I arrived, Marcela had already drunk four glasses of milk.
Explanation: the Spanish plusquamperfect expresses the idea that something occurred before another action in the past. The action to arrive, it happened after the drinking action was over. In English this tense is named past perfect.