The correct answer is option 'C', which is the Free nuclear type of endosperm.

The endosperm is a nutritive tissue found in the seeds of flowering plants. It provides nourishment to the developing embryo in the seed. The endosperm can develop in different ways, depending on the type of division and wall formation that occurs during its development. One of these types is the Free nuclear type.

Here is an explanation of the Free nuclear type of endosperm:

1. Definition:
The Free nuclear type of endosperm is characterized by the absence of cell walls during the early divisions of the primary endosperm nucleus (PEN). The first division of the PEN and a few subsequent divisions occur without the formation of cell walls.

2. Division without wall formation:
In the Free nuclear type, the PEN undergoes several rounds of nuclear divisions without the formation of cell walls. This results in the formation of a multinucleate mass of cytoplasm known as the coenocyte.

3. Increase in nuclear number:
As the divisions progress, the number of nuclei in the coenocyte increases. These nuclei are dispersed throughout the cytoplasm without any definite arrangement.

4. Nuclei migration:
In some cases, the nuclei may migrate towards the periphery of the coenocyte, forming a peripheral layer. In other cases, the nuclei may remain evenly distributed in the cytoplasm.

5. Wall formation:
Eventually, cell walls start to form between the nuclei, dividing the coenocyte into individual cells. The timing of wall formation varies among different plant species. In some cases, wall formation may occur simultaneously around all the nuclei, while in others, it may occur gradually.

6. Importance:
The Free nuclear type of endosperm allows for rapid nuclear divisions and the accumulation of a large amount of cytoplasm, which is essential for providing nutrients to the developing embryo. This type of endosperm is commonly found in plants belonging to families such as Poaceae (grasses) and Solanaceae (nightshades).

In conclusion, the Free nuclear type of endosperm is characterized by divisions of the primary endosperm nucleus without wall formation, resulting in the formation of a multinucleate coenocyte. Eventually, cell walls form, dividing the coenocyte into individual cells. This type of endosperm is important for providing nourishment to the developing embryo in certain plant species.