What does a reed woodwind embouchure require?

The correct answer highlights the fundamental technique necessary for producing sound on a reed woodwind instrument. A reed woodwind embouchure requires the player to enclose the mouthpiece with their lips, creating a seal. This seal is crucial because it ensures that the air blown by the musician is directed through the reed. When the player maintains a proper embouchure, the air pressure causes the reed to vibrate, generating the sound characteristic of instruments like the clarinet or saxophone.

In contrast, the other options do not accurately encapsulate the key aspect of embouchure formation in reed woodwinds. While blowing air across the reed is part of sound production, it does not specifically address the technique required for the embouchure. Using only one hand to hold the instrument is irrelevant to the embouchure technique itself, as both hands are usually needed for proper instrument handling. Lastly, manipulating the reed with fingers does not directly relate to how the embouchure is established and maintained; instead, it focuses on finger positioning, which is separate from the embouchure's role in sound production. Thus, the emphasis on enclosing the mouthpiece is essential for effective sound generation on reed woodwinds.