<span>Because they are not enclosed in a phosoplipid membrane as are other organelles
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The right answer is the mandate to marry within one's tribe. Even though Nnaemeka knew that his decision to marry a woman from another tribe would upset his father, he thought that his annoyance would eventually pass away. But he had not realized that his was a decision without precedent, and this caused surprise, indignation, and sadness among his people, who, stuck to tradition, saw in Nnaemeka's act a reflection of their Lord's cautionary teachings ("Sons shall rise against their fathers") and a bad omen ("It is the beginning of the end"), hence illustrating their conviction in the mandate to marry within one's tribe.
A was the correct answer, hope this help :3
The prepositional phrase in this sentence is c. "to your sentence structure", because it is postmodifying an infinitive phrase (to bring complexity), which has the same value, in this case, as a noun phrase. Besides it is composed by a preposition (to) and a noun phrase (your sentence structure).
Option a. is a verb phrase as well as option b. In the same way, letter d. is not a prepositional phrase as it is an adjective phrase used in the comparative form.
