Q: Which substance in the blood is responsible for transporting oxygen?
Correct: 0 / Attempted: 0
(A) Insulin
(B) Glucagon
(C) Collagen
(D) Hemoglobin
Answer: (D) Hemoglobin Explanation: Hemoglobin is a protein found in red blood cells that binds to oxygen and carries it from the lungs to the rest of the body. Insulin and glucagon are hormones involved in regulating blood sugar, and collagen is a structural protein found in connective tissues.
