Final answer:
In volleyball, serves can be executed using different techniques, not just underhand motions; options include overhand, jump serves, and sidearm techniques, depending on the game's rules and player's preference.
Step-by-step explanation:
In many sports, particularly volleyball, a serve can be made with a variety of techniques and not all serves are required to be performed with an underhand motion. Instead, players may use an overhand motion, a jump serve, or even a sidearm technique, depending on the rules of the game and the player's style and strategic preference. However, in recreational or beginner play, sometimes underhand serves are encouraged or required for ease and safety. In professional and competitive volleyball, the overhand serve is more commonly seen due to the power and speed it can generate, making the serve more difficult to receive.