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: All cnidarians are aquatic., Fact2: Cnidarians are also called coelenterates., Question: What are aquatic? (A) coelenterates (B) trees (C) lizards (D) angiosperm (E) holding nutrients (F) trees and flowers (G) the Sun (H) humans

A: A
****
Q: Fact1: when a metal rusts , that metal becomes orange on the surface, Fact2: Cast-iron and steel surfaces are susceptible to corrosion in the form of rust., Question: Cast-iron and steel surfaces are susceptible to becoming what on the surface? (A) hardness (B) solid (C) irritants (D) acids (E) orange (F) heat (G) Unsafe (H) damaging

A: E
****
Q: Fact1: phase changes do not change mass, Fact2: Melting is a phase change., Question: What does not change mass? (A) an object (B) gravity (C) density (D) bullfrogs (E) Energy. (F) blastoids (G) melting (H) volume

A:
G
****