GM cannot be used as an indicator of stability at all angles of inclination because __________.

Correct Answer: Option D — M is not fixed at large angles

Metacentric height (GM) is valid for small angles of inclination (typically under 7 to 15 degrees) because the metacenter (M) remains fixed. At large angles of heel, the underwater hull form changes significantly, causing the metacenter to shift, meaning M is no longer fixed.