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: Which statement explains why a mother's unhealthy diet during pregnancy is harmful to her embryo's development?  
 (A) The embryo inherits half its chromosomes from its mother. (B) The embryo receives its food from its mother through the placenta. (C) The embryo receives oxygen through the placenta. (D) The embryo receives mutations carried by its mother.

A: B
****
Q: A light-year is a measure of  
 (A) time. (B) energy. (C) distance. (D) direction.

A: C
****
Q: If the climate in an area were to become much drier, which plant variation would be most advantageous to the survival of the species?  
 (A) bigger branches (B) larger flowers (C) thicker leaves (D) longer stems

A:
C
****