What is the instruction given by the musical term 'piano (p)'?

The musical term 'piano (p)' instructs performers to play quietly. This term is a dynamic marking that specifically indicates a softer volume level. In music notation, dynamics are crucial as they help convey the emotional intent and character of a piece. Using 'piano' signals to the musician that they should not only reduce the volume but also consider the overall expression of the music being played.

The other options relate to different expressive terms. For example, 'very loudly' would correspond to the term 'forte,' indicating the opposite of what 'piano' means. Similarly, 'play with excitement' and 'play rapidly' involve different aspects of musical performance that are not indicated by 'piano,' focusing instead on emotional delivery and tempo, rather than dynamic volume. Thus, the instruction 'piano (p)' is a clear call for subdued sound.