What best describes the relationship between the two sets of reactions of photosynthesis, which are the light-dependent reactions and the light-independent reactions?

a. each set produces sugars, and by working together they produce more sugars than they would produce separately.

b. each set produces half of a sugar molecule, and later the two halves are joined together.

c. only the light-dependent reactions produce sugars, but they depend on products of the light-independent reactions.

d. only the light-independent reactions produce sugars, but they depend on products of the light-dependent reactions.