Which instrument sounds down a major ninth from written treble?

• A. Eb alto clarinet
• B. Eb contra alto bass clarinet
• C. Bb tenor sax
• D. Oboe

Answer: (C)

Instruments in the Bb family shift the written pitch to produce concert pitch by a ninth, and the tenor saxophone is the classic example of this: the written note sounds a major ninth lower. So a note written on treble staff for the Bb tenor sax will come out sounding down by a full octave plus a whole step. That’s why the tenor sax is the correct pick here—it matches the specified transposition exactly.

The other options don’t follow this same interval: the Eb alto clarinet transposes by a different interval (not a major ninth), the Eb contra alto bass clarinet also uses a different transposition, and the oboe sounds as written without transposition.