You are given a science question (hard-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.

Students are designing kites to discover what type of kite flies the highest. Which is the most important to consider when designing a kite to fly high?
(A) string length (B) surface area (C) materials used (D) time of day
B

When a mixture of oxygen and hydrogen is ignited in a test tube, the reaction shown occurs. Hydrogen + Oxygen -> Water + Energy What happens to the total mass of the contents of the test tube?
(A) The total mass increases. (B) The total mass decreases. (C) The total mass remains the same. (D) Part of the mass is changed to heat energy.
C

Which would most likely need to happen for a new plant to grow?
(A) Leaves grow out of a stem. (B) Insects get attracted to the petals. (C) A blossom falls into the soil. (D) A seed sprouts into a seedling.
D