Which group includes piano, organ, and harpsichord?

• A. Strings
• B. Woodwinds
• C. Keyboard instruments
• D. Brass

Answer: (C)

Instruments played via a keyboard interface are grouped as keyboard instruments. Piano, organ, and harpsichord all use a keyboard to produce sound, which is why they belong in this category. The sound is produced in different ways on each: the piano uses hammers striking strings, the organ uses air or pipes controlled by keys, and the harpsichord plucks strings when keys are pressed. While a piano does have strings inside, the defining feature for this classification is the keyboard interface, not the presence of strings. Other families—strings, woodwinds, brass—are organized by how the sound is generated rather than by how you play them, making keyboard instruments the correct group for these three.