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.

Question: Which of the following substances can be separated into several elements? (A) nitrogen (B) zinc (C) air (D) aluminum?
separated, several, elements?

Question: Which of these would help to prevent infections from occurring in small cuts and scrapes? (A) apply a cold ice pack (B) raise the injured area (C) apply pressure to stop bleeding (D) wash the area with warm, soapy water?
prevent, infections, cuts, scrapes?

Question: For a technology project, Kyle came up with an idea to build a model bridge. He wants his bridge to span 50 cm and to support a 1 kg object. According to the engineering design process, which of the following should be Kyle's next step? (A) construct prototypes of different kinds of bridges (B) research the different designs of bridges (C) gather the materials needed to build the bridge (D) make a drawing to show how to build the bridge?

model, bridge., span, 50, cm, support, 1, kg, engineering, design, next, step?

