The buildup of lactic acid in muscle cells is caused by

There's not enough oxygen in the muscles to break down glucose and glycogen

Explanation:

Lactic acid buildup occurs when there's not enough oxygen in the muscles to break down glucose and glycogen. This is called anaerobic metabolism.

learn more here:

https://www.sciencedirect.com/topics/medicine-and-dentistry/anaerobic-metabolism

Hope this helps,

H.M.

option a and d is the correct answer

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