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.

[Q]: The ounce, the pound, and the ton are units of  
 (A) time. (B) weight. (C) length. (D) distance.
[A]: B


[Q]: A scientific guess about the cause and effect of an event is called  
 (A) a variable. (B) a theory. (C) a hypothesis. (D) an observation.
[A]: C


[Q]: A student plans to write a report about a type of bird that includes only facts. Which statement should the student leave out of the report?  
 (A) These birds are blue. (B) These birds are beautiful. (C) Most of these birds are 13 cm tall. (D) Most of these birds are about 10 grams.
[A]:
B