The exchange of gases and other materials between cells in the body and cells in the blood occurs in...

A. stomach
B. capillaries
C. arteries
D. veins

The answer is B.)Capillaries

Exchange of Gases, Nutrients, and Waste Between Blood and Tissue Occurs in the Capillaries. Capillaries are tiny vessels that branch out from arterioles to form networks around body cells. In the lungs, capillaries absorb oxygen from inhaled air into the bloodstream and release carbon dioxide for exhalation.
(Don’t know if you wanted all that)

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