Read the passage to answer the question. Will give 20 points i need awnser now
Vegetable farmers often plant soybeans every few years. Rotating crops breaks up the life cycles of many insect pests, and the soybean plants provide the soil with nitrogen. Other crop plants need the nitrogen to grow well. A field of soybean seeds has been planted on a farm in Indiana. As soon as the first leaves emerge from the seed, photosynthesis begins.

Which substance is the chemical food source for the soybean plants?

A. glucose

B. sunlight

C. water

D. carbon dioxide