In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").

[EX Q]: Fact1: Echinoderms lack a centralized nervous system., Fact2: Sand dollars and sea biscuits are also echinoderms., Question: What lacks a centralized nervous system? (A) Damaged hearing (B) Humans (C) Horses (D) Sand dollars (E) insects (F) Chickens (G) Pesticides (H) barnacles
[EX A]: D

[EX Q]: Fact1: a greenhouse is used to protect plants by keeping them warm, Fact2: With lots of rain and a warm climate, plants grow well., Question: What does a greenhouse help plants do? (A) Park cars (B) Start panicking (C) reproduce (D) growth (E) Bloom slower (F) adding heat (G) Regrows it (H) Grow well
[EX A]: H

[EX Q]: Fact1: Population density is the average number of individuals per unit of area or volume., Fact2: Another measure of growth is population density., Question: What can be determined by the average number of people per one unit of area? (A) hygeine (B) emissions (C) animals (D) growth (E) forces (F) health (G) education (H) people
[EX A]:
D