Which sentence is an example of an objective summary? O Elizabethans had some interesting ideas about disease.
Malaria was common in marshy areas where mosquitoes bred.
Studying humors seems like a ridiculous medical practice.
Obviously, English citizens should have left the swampy regions.

The sentence that is an example of an objective summary is:

B. Malaria was common in marshy areas where mosquitoes bred.

Explanation:

When a sentence is subjective, it expresses the opinion and feelings of the speaker. That means it is biased - it doesn't stick only to the facts, but allows preconceptions and opinions to permeate it. That is what happens in the first, third, and last options provided. The subjectivity in those sentences can be identified because of the use of the words "interesting", "ridiculous" and "obviously", which help convey the speaker's feelings and ideas.

On the other hand, the second option is an example of an objective sentence. Unlike the others, it sticks to facts only. There is not a single word or phrase focusing on the speaker's opinion on the subject. Therefore, it is the correct answer.

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