Explanation
A plant develops a seed from the ovule. Therefore, the correct option is C: Ovule.
The ovule is a structure that is part of the female reproductive system of a plant. It contains the female gametophyte, which includes the embryo sac that houses the egg cell. After fertilization, the zygote develops into an embryo, and the ovule develops into a seed that contains the embryo and endosperm.
The ovary is another structure that is part of the female reproductive system of a plant. It contains one or more ovules and, after fertilization, it develops into a fruit that contains the seeds. However, the seed itself is developed from the ovule.