A dehydration synthesis reaction is also known as:

Options

A. a condensation reaction
B. a hydrolysis reaction
C. an isomeric reaction
D. an energy-releasing reaction

Explanation

### Step-by-Step Solution:

1. **Understanding Dehydration Synthesis**:
- A dehydration synthesis reaction involves the joining of two smaller molecules to form a larger molecule. During this process, a water molecule is removed.

2. **Identifying Key Terms**:
- The term "dehydration" refers to the removal of water. "Synthesis" indicates that a new compound is being formed.

3. **Recognizing Alternative Names**:
- Dehydration synthesis is often referred to by another name due to the nature of the reaction. This alternative name is associated with the process of combining molecules while losing water.

4. **Conclusion**:
- The correct term that is synonymous with dehydration synthesis is "condensation reaction." Thus, a dehydration synthesis reaction is also known as a condensation reaction.

### Final Answer:
A dehydration synthesis reaction is also known as a **condensation reaction**.

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