Which Region of a Sarcomere Contain Thin Filaments

Question

Which region of a sarcomere contain thin filaments?
A)I band
B)A band
C)H zone
D)Both I band and A band.

Accepted Answer

The I band contains only thin filaments, while the A band contains both thin and thick filaments. The overlap of thin and thick filaments in the A band contributes to muscle contraction, but the I band is unique in that it only contains thin filaments.