Which is the main arena of cellular activities?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the main area where cellular activities occur. The term "arena" refers to a place or environment where activities take place.

2. **Identifying the Main Arena**: In the context of a cell, the main arena of cellular activities is the **cytoplasm**. This is true for all types of cells, including prokaryotic cells (like bacteria), eukaryotic cells (like plant and animal cells).

3. **Defining Cytoplasm**: The cytoplasm is a jelly-like substance found within the cell membrane. It is composed of cytosol (the liquid part) and various organelles (the specialized structures within the cell).

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