The correct inference is:
D. roots are underground and are not exposed to sunlight.
Chloroplasts are the organelles in plant cells that carry out photosynthesis, a process that requires sunlight. Since root cells are typically located underground, they do not receive sunlight and therefore do not need chloroplasts for photosynthesis. Instead, root cells primarily focus on the absorption of water and nutrients from the soil, which is achieved through other specialized structures and functions.