How many of the above are products of volcanic eruptions?

Explanation:

1. Pyroclastic debris: This is indeed a product of volcanic eruptions. Pyroclastic debris consists of rock fragments and hot gases ejected from a volcano during an explosive eruption.

2. Ash and dust: These are also products of volcanic eruptions. Volcanic ash is composed of fine particles of pulverized rock, minerals, and volcanic glass created during eruptions.

3. Nitrogen compounds: While volcanoes do emit some nitrogen compounds, primarily in the form of ammonia (NH3), they are not considered a major source of nitrogen emissions compared to other volcanic products.

4. Sulphur compounds: Volcanoes are significant sources of sulphur compounds, particularly sulphur dioxide (SO2). These emissions can have substantial impacts on climate and air quality.

Therefore, the correct answer is: (d) All four