You are given an elementary science question along with a few answer options. List all the words from the question that are essential and sufficient for choosing the correct answer option. Keep in mind that essential words are necessary to understand the meaning of the given question. However, non-essential words provide little information needed to select the correct answer. You can think about it like this: If the question was in another language, knowing the meaning of which words were necessary and enough for you to understand the question and answer it?. If your answer consists of multiple spans of words from the question, separate those using a comma (", "). Do not generate any word that is not present in the question. Make sure that your response is contained in the given question and the words are in the same order as the question.
 Grammatical correctness is not important.

[Q]: Question: When a substance undergoes a change and a new substance is formed with different physical and chemical properties, the change is called ___. (A) nuclear (B) chemical (C) reversible (D) physical?
[A]: change, new, substance, formed, different


[Q]: Question: Skyler is selecting the kind of paper he wants to use to make a greeting card. He wants to select paper that does not tear easily. Which of the following features of the paper is most important for Skyler to consider? (A) color (B) size (C) smoothness (D) thickness?
[A]: paper, tear, easily., features, important


[Q]: Question: A scientist is studying small insects. Which of the following is the best estimate of the LENGTH of a ladybug? (A) 10 cm (B) 5 cm (C) 10 mm (D) 5 mm?
[A]:
small, insects., LENGTH, ladybug?