The glucose molecules having a carbons? A. 6 B. 7 C. 5 D. 4

The correct answer is A. Glucose is a six-carbon sugar. It is the most abundant monosaccharide in the human body and is the main source of energy for cells. Glucose is also a key component of starch and glycogen, which are storage forms of carbohydrates.

Option B is incorrect because glucose does not have seven carbons. Option C is incorrect because glucose does not have five carbons. Option D is incorrect because glucose does not have four carbons.