Later, makers added keys to the contrabassoon to facilitate its playing and intonation. t/f

The correct answer is:

True

Explanation:

The contrabassoon design was initially based in an Egyptian instrument constructed with some holes for the production of sounds, they used to have different sizes of the instrument in order to have a wide range of sounds. Later on,  the instrument evolved and it was Alfranio Canon de Ferrara who developed the current Basson design which has the same shape of the contrabassoon, however, this second instrument is characterized for its smaller shape. Some years later, the contrabassoon got the keys for a better performance and intonation.