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").

[Q]: Fact1: a prism is used for refracting light, Fact2: Refraction is the bending of light cause by a speed change when it passes through different media., Question: What aspect of light changes when it passes from air into a prism? (A) power (B) seasons (C) speed (D) energy (E) a wave (F) Joules (G) heat (H) unique
[A]: C


[Q]: Fact1: Flagella help prokaryotes move., Fact2: Most prokaryotes are unicellular., Question: What helps unicellular organisms move? (A) evaporation (B) bacteria (C) heat energy (D) glucose (E) sweating (F) flagella (G) legs (H) blood
[A]: F


[Q]: Fact1: Vertebrates are animals that have a backbone., Fact2: Invertebrates have no vertebrae or backbone., Question: What do some animals not have? (A) nucleus (B) fish (C) offspring (D) vertebrae (E) Chlorophyll (F) invertebrates (G) Energy (H) Energy.
[A]:
D