Topic: Conjunction,

Best Answer Explained in Below-:

The sentence “------- living in the water, whales breathe air” presents a contrasting relationship between whales' aquatic environment and their biological need for air. The correct option, “Despite,” indicates that although whales inhabit an aquatic habitat, they still require air for respiration, which is noteworthy because it challenges a common assumption that creatures living in water can breathe underwater.

“Despite” is a conjunction used to introduce a contrasting statement; it highlights an unexpected relationship between two ideas. In this case, the contrast arises from the notion that living in the water typically suggests a dependence on gills for breathing, which is not applicable to whales, as they are mammals that need to surface for air.

Other options, such as “For” and “Though,” do not convey the same emphasis on contrast. “For” suggests causation rather than contrast, while “Though” would require structural adjustments to fit grammatically in the sentence. “Now” does not relate to the contrasting ideas of habitat and respiratory needs.

In summary, “Despite” best captures the essence of the relationship in the sentence, making it the appropriate choice.