It's D. Sparkled, twinkled and glittered all indicate a sort of flashing light, but sparkled and twinkled are both too, uh, cheerful. I mean, if she was crying tears of happiness, then sparkled would be appropriate, but I'm guessing that's not the case. You wouldn't usually use the word 'twinkle' for reflected light. And tears can't radiate, of course. Light can radiate, but that would be a constant light source, which you wouldn't get from a reflection off a drop of water.

I would pick D. I will admit it is a tough multiple choice question. Twinkled sounds too positive and since she heard bad news, glittered might be the best option. They could all be positive in a way. I think it's a matter of opinion.