With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Heavy water lacks the characteristic blue color of light water; this is because the molecular vibration harmonics, which in light water cause weak absorption in the red part of the visible spectrum, are shifted into the infrared and thus heavy water does not absorb red light.
text_B: Heavy water absorbs what kind of light?
DON'T KNOW.