Question

In which passage is it clearest that the author is using diction to achieve some kind of effect?

Answer 1

Diction is the choice of words to achieve a special effect. A characteristic of  diction is a common use of adverbs and metaphors. This can be found in option B: 

the words "gingerly", "sleepy", "like a mouse" don't introduce (a lot of ) new information, but create the atmosphere of coziness and sleepiness.