Which of the following is NOT a primary product of an explosion?

In the context of explosion dynamics, the primary products of an explosion are the immediate and direct effects that result from the rapid expansion of gases and the release of energy. These typically include blast waves, heat, and fragmentation.

Blast is the shockwave that radiates outward from the center of the explosion, causing pressure fluctuations that can lead to destruction. Heat represents the intense thermal energy released, which can ignite materials and cause burns or fires. Fragmentation refers to the pieces of the explosive material or surrounding structures that are propelled away from the explosion, posing a risk of injury or damage.

While sound is a noticeable effect of an explosion, it is a secondary consequence rather than a primary product. The sound is a result of the rapid changes in pressure and the propagation of sound waves created by the explosion, but it does not contribute to the physical effects (such as damage or injury) in the same direct way that blast, heat, and fragmentation do. Therefore, identifying sound as not being a primary product of an explosion is accurate.