What structure protects insects and gives them muscles

Which must be kept in mind when determining if an explanation is correct? check all that apply.which must be kept in mind when determining if an explanation is correct? check all that apply.

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Which of these statements is true about autotrophs, but not heterotrophs? a. they use sugar and oxygen to make carbon dioxide and water.b. they use chlorophyll and oxygen to make carbon dioxide and water.c. they use sunlight, water, and carbon dioxide to make sugars.d. they use sunlight, water, and oxygen to make chlorophyll.