Unicellular organisms have one-celled body. (T / F)

Explanation

**Step-by-Step Solution:**

1. **Understanding Unicellular Organisms**: The term "unicellular" refers to organisms that consist of only one cell. This means that their entire body is made up of a single cell.

2. **Confirming the Statement**: The statement in the question claims that unicellular organisms have a one-celled body. Since unicellular organisms are defined by having only one cell, the statement is true.

3. **Examples of Unicellular Organisms**: A common example of a unicellular organism is amoeba. Amoeba is a single-celled organism that performs all necessary life functions within that one cell.

4. **Life Processes in Unicellular Organisms**: All life processes such as digestion, respiration, and excretion occur within the single cell of a unicellular organism. This further supports the idea that their body is indeed made up of one cell.

5. **Conclusion**: Based on the definition and characteristics of unicellular organisms, the statement that "unicellular organisms have one-celled body" is true.

**Final Answer**: True (T)

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