What environmental factors must a sniper consider before firing?

• A. Elevation, visibility, and number of enemies
• B. Wind speed and direction, temperature, humidity, and elevation
• C. Lighting conditions and background noise
• D. Weather and terrain type

Answer: (B)

The correct answer is focused on the critical environmental factors that significantly influence a sniper's shooting accuracy and effectiveness. Wind speed and direction are pivotal because they affect the bullet's path after it leaves the muzzle, requiring precise adjustments to ensure the projectile reaches its intended target. Additionally, temperature can impact bullet velocity and performance, as colder air can result in denser air that slows down the bullet, while a warmer environment can have the opposite effect.

Humidity plays a role as well, as higher moisture levels can increase air density and also slightly affect a bullet's flight. Elevation is important because it influences the atmospheric pressure and, consequently, the bullet’s trajectory. At higher elevations, there is less air resistance, which can change the way a bullet behaves in flight.

In comparison, while options that mention enemies, lighting conditions, or terrain type are important in the broader context of a sniper's operations, they do not directly impact the physical ballistics involved when taking a shot. Thus, the considerations listed in the correct answer encompass the essential atmospheric conditions that directly affect firing accuracy.