C. CO2 diffuses by way of the stomata.
Carbon dioxide enters the plants through its leaves. Present under the surface of leaves are small holes through which carbon dioxide diffuses into the plant to fulfil its requirements. The leaf also gives off oxygen from these same holes in the leaves. These small holes are called stomata which is the plural form. the singular form of this word, or a single hole on the underside of the leaf is called a stoma.
