Components seen in a slide of human cheek cell when observed under a microscope:

Cell membrane:
- The cell membrane is a thin, flexible barrier that surrounds the cell and separates its internal components from the external environment.
- It is composed of a phospholipid bilayer with embedded proteins that control the movement of substances in and out of the cell.

Cytoplasm:
- The cytoplasm is the gel-like substance that fills the cell.
- It contains various organelles, such as mitochondria, endoplasmic reticulum, Golgi apparatus, and ribosomes.
- It also contains cytosol, which is the fluid portion of the cytoplasm that suspends the organelles.

Nucleus:
- The nucleus is the control center of the cell.
- It contains the cell's genetic material in the form of DNA.
- The nucleus is enclosed by a nuclear membrane and contains a nucleolus, which is involved in the production of ribosomes.

Explanation of the correct answer:

The correct answer is option C, which includes the cell membrane, cytoplasm, and nucleus. This is because these three components are commonly found in animal cells, including human cheek cells.

The cell membrane is a characteristic feature of all cells and is responsible for maintaining the integrity of the cell by controlling the movement of substances in and out of the cell.

The cytoplasm is the site of many cellular activities and contains various organelles that perform specific functions. It is a gel-like substance that fills the cell and provides support to the organelles.

The nucleus is the control center of the cell and contains the genetic material. It regulates the cell's activities and is involved in the transmission of genetic information during cell division.

The other options are incorrect:

Option A (cell wall, cytoplasm, nucleus) is incorrect because animal cells, including human cheek cells, do not have a cell wall. Cell walls are present in plant cells but not in animal cells.

Option B (cell membrane, protoplasm, nucleus) is incorrect because the term "protoplasm" is outdated and not commonly used. The cytoplasm is the correct term to describe the gel-like substance that fills the cell.

Option D (cell wall, protoplasm, nucleus) is incorrect because, as mentioned earlier, animal cells do not have a cell wall.