The correct answer is Option A: Nucellus. Here's why:

The ovule is the structure within the ovary of a flower that develops into a seed after fertilization. Let's break down the parts of an ovule and their functions:

1. Nucellus:

• This is the central core of the ovule.
• It is composed of parenchyma cells, which are specialized cells that store nutrients.
• The nucellus provides nourishment to the developing embryo sac (female gametophyte) and ultimately the developing embryo.

2. Integuments:

• These are protective layers that surround the nucellus.
• They develop into the seed coat (testa) after fertilization, protecting the seed.

3. Placenta:

• This is a tissue within the ovary that connects the ovule to the ovary wall.
• It plays a crucial role in the transport of nutrients and water to the developing ovule.

4. Funicle:

• This is the stalk that attaches the ovule to the placenta.

In summary, the nucellus is the part of the ovule that specifically stores reserve food materials to support the development of the embryo within the seed.