Which is the most logical placement for sentence 7 (reproduced below)?
The nectarine is a hybrid fruit.

Sentence 7 is most logical where it is now in the passage, as it helps define “nectarine” in sentence 6 and sets up the description of the nectarine’s composition in sentence 8.
After sentence 3 is incorrect because placing sentence 7 after sentence 3 would both interrupt the narrative of the founding and early success of Kim Brothers and disrupt the flow between sentences 6 and 8.
After sentence 10 is incorrect because placing sentence 7 after sentence 10 would both disrupt the flow between sentences 6 and 8 and introduce basic information about the nectarine later in the passage than is required by the writer’s development of the topic.
After sentence 11 is incorrect because placing sentence 7 after sentence 11 would both disrupt the flow between sentences 6 and 8 and interrupt the narrative of the later history of Kim Brothers.