Which detail from the passage demonstrates a subjective perspective? “Through the midst of the city [Baghdad] flows a very large river”
“from Baghdad to the sea is a journey of fully eighteen days”
“Merchants travelling to India follow this river to a city called Kais”
“in groves all around Basra grow the best dates in the world”

D. “in groves all around Basra grow the best dates in the world”

Explanation:

Perspective based on the question could either be subjective or objective, subjective perspective has to do culled or extracted opinions based on personal volition, belief or desire. In most cases, subjective opinions aren't physically measurable as facts used to backup such opinion might be based on sentiment or exposure. Objective perspective on the other hand is usually well established as opinions of this sort can be physically evaluated. Hence, from the passage, the sentence, “in groves all around Basra grow the best dates in the world" is based on subjective perspective.

because each is self-sufficient.  

to convince americans of the importance of others.