instruction:
You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.
question:
Amylase is a chemical that decomposes starch into maltose and dextrin. Which best describes the role of amylase in the human body?  
 (A) as an inhibitor of insulin production (B) as an enzyme that aids in digestion (C) as a catalyst for protein synthesis (D) as a receptor of fatty acid chains
answer:
B


question:
Which set contains kingdoms that contain only heterotrophs?   
 (A) Protists, Fungi (B) Bacteria, Animals (C) Plants, Fungi (D) Animals, Fungi
answer:
D


question:
Researchers are developing new types of crop plants with desirable characteristics such as disease resistance and drought tolerance. Crossing plants so that the next generation will express desirable traits is best described as  
 (A) selective breeding. (B) natural selection. (C) genetic engineering. (D) gene sequencing.
answer:

A