What does "gesangvoll" mean in a musical context?

In a musical context, “gesangvoll” translates to "in a singing style." This term originates from German, where "gesang" means "song" or "singing." When composers instruct performers to play "gesangvoll," they are suggesting that the music should be performed with a lyrical quality reminiscent of singing. This means that the instrumental execution should be expressive and lyrical, emphasizing melodic lines and phrasing as one would do when singing.

The other options do not capture this specific musical nuance; while they convey different aspects of musical expression, they do not relate directly to the emphasis on a singing style that "gesangvoll" embodies. Smoothly might suggest a legato approach, joyfully relates more to the emotional character of the music, and energetically implies a certain tempo and vigor rather than the melodic emphasis implied in singing. Thus, the focus on a singing quality makes the correct answer particularly fitting in this context.