Task: Question Answering
Input (English): Which sentence best describes the organization of the heart?  
 (A) The heart is an organ made up of different types of tissues, each of which has different types of cells. (B) The heart is a tissue made up of different types of organs, each of which has different types of cells. (C) The heart is a system made up of one type of tissue and identical cells. (D) The heart is a tissue made up of one type of organ and identical cells.
Output (English): A