Task: Question Answering
Input (English): During a lab investigation a scientist heats a solid substance. The scientist observes that the solid has two different melting points. The scientist is able to separate the two resulting liquids. Which statement best classifies the original solid substance?     
 (A) It was an atom. (B) It was a mixture. (C) It was an element. (D) It was a compound.
Output (English): B