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 Input:
Fact1: Many corals secrete an exoskeleton that builds up to become a coral reef., Fact2: Good examples are Bubble coral, Elegance coral, Frogspawn and other Euphyllia corals., Question: What is secreted by organisms like frogspawn to become a reef? (A) exocrine glands (B) food and shelter (C) exoskeleton (D) bones (E) Energy (F) Chemical energy (G) plasma (H) Energy.

Ex Output:
C


Ex Input:
Fact1: Fertilization occurs when sperm swim to an egg inside an archegonium., Fact2: Gametes in males are called sperm, and in women commonly referred to as eggs., Question: What occurs when a male gamete swims to an egg? (A) permineralization (B) competition (C) movement (D) rapid expansion (E) fertilization (F) birth (G) copulation (H) ovulation

Ex Output:
E


Ex Input:
Fact1: fluoride decreases tooth decay, Fact2: Tooth decay is a destruction of the tooth enamel., Question: What prevents the destruction of tooth enamel? (A) protection (B) treatment (C) Flouride (D) the cervix (E) keratin (F) estrogen (G) Soda (H) Nitrogen

Ex Output:

C