D). In Heart of a Samurai, Manjiro is faced with grave dangers, such as finding enough food to survive and swimming to the boats filled with barbarians.
Explanation:
The last choice most aptly revises sentence 3 as it is grammatically and lexically coherent. <u>The use of commas after the introductory prepositional phrases and before the beginning of examples('such as....barbarians') is appropriate which clearly signifies the separation of words/phrases and makes the meaning more clear and evident for the readers to understand</u>. Thus, <u>option D</u> is the correct answer.
