Which inversion places the seventh in the bass?

• A. Root Position
• B. First Inversion
• C. Second Inversion
• D. Third Inversion

Answer: (D)

In seventh chords, the bass note changes with each inversion, and the one that places the seventh in the bass is the third inversion. That happens because the inversions are named by which chord tone sits in the bass: root position has the root in the bass, first inversion puts the third in the bass, second inversion puts the fifth in the bass, and third inversion puts the seventh in the bass.

For example, a C7 chord is C–E–G–Bb. In root position the bass is C; in the first inversion the bass is E; in the second inversion the bass is G; in the third inversion the bass is Bb, which is the seventh. So the third inversion is the one where the seventh is in the bass. This holds for any seventh chord, not just C7.