I am pretty confident that the answer is D) mouthpieces for breathing. This is the only way they can stay underwater for long periods of time. If they came up every 10 seconds for breath, they would waste a lot of time.
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Answer:
What are the other options ?
Explanation:
Answer:
A) Vitamin A
Explanation:
Dark green vegetables are a good source of Vitamin A, and do not contain much, if any, Vitamin D, zinc, or selenium.
