单项选择题
Which is the phosphorylation step of fructose metabolism in muscle?()
A. Fructose→ fructose 1-phosphate
B. Fructose 1-phosphate→glyceraldehyde + dihydroxyacetone phosphate
C. Glyceraldehyde→ glyceraldehyde 3-phosphate
D. Mannose→mannose-6-phosphate