Which statement describes a modulating sequence?

• A. The second segment moves to a different tonal center than the first.
• B. The second segment is exact intervallic transposition of the first.
• C. Only part of first segment is transposed.
• D. First segment is transposed but kept in diatonic scale.

Answer: (A)

A modulating sequence happens when a motif is repeated at successive pitch levels while the center of gravity—the tonal center or key—shifts from one segment to the next. In other words, the material isn’t just moved up or down within the same key; the overall tonal center changes, giving a sense of modulation as the sequence progresses.

The statement that the second segment moves to a different tonal center than the first captures this idea directly: you hear a deliberate shift in key, not just a transposition within the same key.

By contrast, if the second segment is simply an exact intervallic transposition of the first, the tonal center stays the same even though the pitches are moved; there’s no modulation. If only part of the first segment is transposed, that isn’t the regular pattern of a sequence, and if the first segment is transposed but kept within the diatonic scale, the material remains rooted in the same key area rather than moving to a new one.