Identify the structure labeled D

Could someone me with number one you

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )

What causes eclipses? check all that apply. earth's rotation on its axis moon's shadow covering the sun earth's shadow covering the moon earth's orbit and moon's orbit occasionally aligning the moon and sun's gravity pulling in the same direction