Match the compounds (A) ethanol, (B) methane, (C) ethanoic acid, (D) ethyne and (E) ethene with the descriptions given below:
It gives a red precipitate with ammoniacal solution of copper (I) chloride.

Explanation

To solve the question, we need to identify which compound among ethanol, methane, ethanoic acid, ethyne, and ethene gives a red precipitate with ammoniacal solution of copper (I) chloride.

### Step-by-Step Solution:

1. **Understanding the Reaction**: The question states that a compound gives a red precipitate when treated with ammoniacal solution of copper (I) chloride. This reaction is characteristic of terminal alkynes.

2. **Identifying Terminal Alkynes**: Among the given compounds, we need to identify if any of them are terminal alkynes. Terminal alkynes have a triple bond between carbon atoms and at least one hydrogen atom attached to one of the carbons involved in the triple bond.

...