Question

complete the sentence with the better correlative conjunctions.
most vertebrates can perceive the same five flavors that humans can: bitter, salty, sour, sweet, and umami. however, genetic research indicates that _ whales _ dolphins are unable to taste any flavor other than salty.
either...or
both...and

Explanation:

• "either...or" implies a choice between two things. But the sentence states that both whales and dolphins are unable to taste flavors other than salty.
• "both...and" is used to refer to two things together. In this context, it correctly indicates that whales and dolphins (two groups) share the inability to taste flavors other than salty.

Answer:

both...and