Final answer:
Early brass bands consisted of brass wind instruments such as trumpets, trombones, and tubas, using valves and slides to alter pitch.
Step-by-step explanation:
Early brass bands consisted primarily of brass wind instruments. The correct answer to which instruments did early brass bands consist of is b) Trumpets, trombones, and tubas. These instruments are modified tubes with valves or slides used to change the length of the resonating air column, thereby altering the pitch of the sound produced.
For instance, in a trombone, a sliding tube allows the player to vary the tube length and pitch, whereas trumpets and tubas use valves for the same purpose. These brass instruments have been a fundamental part of military and civilian bands, offering a range of sounds from the high-pitched brilliance of the trumpet to the deep, resonant tones of the tuba.