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: adding salt to a solid decreases the freezing point of that solid, Fact2: When seawater freezes, salt is expelled from the solid in a concentrated salt solution called brine., Question: What happens to salt in seawater as it freezes at the freezing point? (A) vaporization (B) boiling (C) expelled (D) salinity (E) evaporation (F) less water (G) water vapor (H) Temperature
A:
C