Timothy most likely warns Phillip to avoid swimming in the water because ____.

A. He sees sharks swimming very close to the shoreline
B. He knows that there are moray eels living in the crevices
C. German submarines may detect they are on the island*****
D. The birds have their nesting grounds on the beach nearby

It has be C, I think?

To determine the correct answer, let's analyze the options and use the information given to find the best choice.

Option A states that "Timothy sees sharks swimming very close to the shoreline." However, there is no given information that suggests Timothy sees sharks.

Option B states that "there are moray eels living in the crevices." While it is possible for this to be a reason to avoid swimming, the passage does not mention anything about crevices or eels.

Option C states that "German submarines may detect they are on the island." Although there is no direct mention of German submarines, this option aligns with the passage's context. The passage describes how Timothy and Phillip are stranded on an island during World War II and are trying to avoid being detected by enemy forces. So, it is likely that Timothy warns Phillip to avoid swimming in the water because they fear being detected by German submarines.

Option D states that "the birds have their nesting grounds on the beach nearby." While this could be a reason to avoid swimming near the beach, it is not directly related to Timothy's warning about potential dangers.

Given the context of the passage, option C seems to be the most likely reason why Timothy warns Phillip to avoid swimming in the water.