One of the following is present in animal cells only:Cell wallPlastidsCentrioleChloroplast

The correct answer is Centriole.

Step 1: Understand the question. The question is asking which of the listed cell components is found only in animal cells.

Step 2: Analyze each option.

• Cell wall: This is not correct because cell walls are found in plant cells, not animal cells.

• Plastids: This is also incorrect. Plastids, including chloroplasts, are found in plant cells where photosynthesis occurs.

• Centriole: This is correct. Centrioles are found in most animal cells, but not in most plant cells. They are involved in cell division.

• Chloroplast: This is not correct because, like plastids, chloroplasts are found in plant cells where photosynthesis occurs.

So, the answer is Centriole.