Consider the following: 1. Pyroclastic debris 2. Ash and dust 3. Nitrogen compounds 4. Sulphur compounds. How many of the above are products of volcanic eruptions?

1. Pyroclastic debris — Yes. Volcanic eruptions eject fragmented rock material like bombs, lapilli and pyroclastic debris. Verdict: Correct.

2. Ash and dust — Yes. Fine volcanic ash and dust are common solid products of eruptions. Verdict: Correct.

3. Nitrogen compounds — Yes. Volcanoes release gases containing nitrogen in small amounts, including nitrogen compounds/ammonia traces. Verdict: Correct.

4. Sulphur compounds — Yes. Sulphur dioxide and hydrogen sulphide are well-known volcanic gases. Verdict: Correct.

Hence, all four are products of volcanic eruptions.