Either the violin or the harpsichord.
the piano
Harpsichord
The most common instrument (tool) is a tape measure.
the most common instrument are titi poke mo at iba pa :D
violin
Trumpet
a piano
The most common instrument played by children between the ages of five and eighteen is the piano. guitar comes in second but it is definitely the piano!
A Telescope.
Guitar!
The most common instrument would have to be trumpet. Answer: Just a guess, but drum. They predate the trumpet and come in many varieties. Indigenous peoples had drums.
Saxophone and the piano.