When sighting in a rifle, which factors should be considered?

When sighting in a rifle, the most relevant factors to consider relate directly to how the bullet will travel and behave in the atmosphere. Gravity plays a significant role because it affects the bullet's trajectory, causing it to drop over distance. Air resistance also impacts the bullet as it travels; it slows down and can alter its path slightly. Energy loss refers to how the bullet’s kinetic energy diminishes as it travels, which affects its accuracy and impact point at various distances.

Understanding these physical principles is crucial for achieving accuracy when aiming at your target. Shooters must account for the way bullets interact with the environment in order to adjust their aim appropriately for distance and wind conditions. The other options, while they may influence shooting in some capacity, do not directly relate to the mechanics of bullet trajectory and accuracy in the same fundamental way that gravity, air resistance, and energy loss do.