I'm not sure but is it being implied?
first i want to tell noun
in the passage there are so many noun like
olive,fruits,grapes,juice,green,purple,black,thousand,tree,persons
Selection is the awful process of weeding the unhealthy (and unnecessary) prisoners from the healthy (and useful) prisoners.
The correct answer is D. This sentence is a perfect example of parallel structure because either after and before AND it in both cases uses simple past tense verbs which are LEARNED AND TRAVELED. The other sentences never show parallelism due to their units are never the same. For example, in letter A , it uses a verb in simple present WALKS AND a progressive tense verb which is TAKING. So, to sum up, for a sentence to be considered parallel, it must be coherent in its structure and internal words. They need to have harmony and unity in tenses as well.
