Which excerpt from "Harrison Bergeron" best illustrates irony?

AHazel had a perfectly average intelligence, which meant she couldn't think about anything except in short bursts.

BThere were tears on Hazel's cheeks, but she'd forgotten for the moment what they were about.

CAnd she had to apologize at once for her voice, which was a very unfair voice for a woman to use. Her voice was a warm, luminous, timeless melody.