What type of ammunition is used for observation of fire, incendiary effects, signaling, and training?

The use of the M62 type of ammunition is specifically designated for purposes such as observation of fire, incendiary effects, signaling, and training exercises. This ammunition is designed to produce a visible effect, making it ideal for scenarios where observing the impact of fire is essential. The incendiary capabilities of the M62 also allow it to demonstrate fire effects effectively, which is useful during training to illustrate principles of artillery fire and target engagement.

In contrast, the other types of ammunition serve different purposes. For example, the M80 is typically used for standard military applications, and the M67 is primarily an anti-personnel weapon, while the M19 has uses more aligned with specific combat scenarios rather than observation and signaling. Thus, the M62 stands out as the appropriate choice for the specified functions in the question.