Hm, are you sure you got the question right? Because all of the sentences are written in active voice! Active voice is essentially everything that is not in the passive voice, and I don't see any passive voice here.
Passive voice would be formed with subject+form of "to be" + past participle,
and we have no example of this. All of the sentences here are in active voice.
What passage specifically? There’s no picture so we won’t be able to help you
b. The coffee taster will <em>prove</em> each batch to be sure that it is robust and full-flavored. This option is the correct one.
The word <em>prove </em>in the second line of the stanza is used to mean <em>taste . </em>Coffee can be tasted, and the poet wants his beloved to taste /prove the pleasures of nature: " ......valleys, groves , hills....yields."
