What defines a rifle in terms of its design and intended use?

A rifle is specifically defined by its design and intended use as a firearm that is typically shouldered and is engineered to fire a single projectile with high accuracy. This characteristic is essential for distinguishing rifles from other types of firearms. When shouldered, the rifle allows the shooter to achieve better stability and control, which enhances precision when aiming at a target.

The mechanism of firing a single projectile, rather than multiple projectiles at once, is also a key defining feature. This design is what enables rifles to be used effectively in a variety of shooting disciplines, including hunting and marksmanship, where accuracy and distance are critical factors.

The other options do not accurately capture the essential attributes of a rifle. While firearms may be designed to be fired with both hands or for various purposes, it is the shoulder-fired, single projectile firing mechanism that specifically characterizes a rifle. The description regarding firing multiple projectiles simultaneously pertains more to shotguns or certain types of weaponry, and the emphasis on accuracy at close range does not align with the general use of rifles, which are often effective at much greater distances.