Which of the following bows is noted for its lightweight and powerful design?

The correct answer is the compound bow, which is distinguished by its innovative design that incorporates a system of pulleys and cams. This mechanism not only allows for a significant reduction in the force required to hold the bow at full draw, making it easier for the archer to aim and shoot, but it also enhances the bow's overall power and efficiency. The lightweight materials used in constructing modern compound bows contribute to easier handling and transport, making them a popular choice among hunters.

In contrast, recurve bows and longbows, while effective for various archery applications, typically rely on more traditional designs and materials that may not provide the same level of power-to-weight ratio. Flat bows also have a unique construction but do not usually incorporate the mechanical advantages found in compound bows. Thus, when looking for a bow that is both lightweight and powerful, the compound bow stands out as the best option.