Acetylcholine is released at the ending of which type of nerve fibres?

Explanation

**Step-by-Step Solution:**

1. **Understanding Acetylcholine**: Acetylcholine is a neurotransmitter, which means it is a chemical messenger released by nerve cells to transmit signals to other cells, including neurons, muscle cells, and gland cells.

2. **Identifying Nerve Fibers**: The question specifically asks about the type of nerve fibers that release acetylcholine. Nerve fibers can be classified into different categories based on their functions, such as sympathetic and parasympathetic fibers.

3. **Parasympathetic Nerve Fibers**: Among these classifications, acetylcholine is primarily released at the endings of parasympathetic nerve fibers. These fibers are part of the autonomic nervous system and are responsible for various involuntary functions in the body.

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