Final answer:
The correct option to correct the shift of voice in the sentence is B: 'While some people gather empty yogurt containers, others collect used Band-Aids.'
Step-by-step explanation:
The correct answer to correct the shift of voice in the sentence 'While some people gather empty yogurt containers, used Band-Aids have also been collected' is option B: 'While some people gather empty yogurt containers, others collect used Band-Aids.'
This sentence maintains the active voice throughout, with the subject 'some people' performing the action of gathering yogurt containers and others performing the action of collecting used Band-Aids.
The other options introduce passive voice or rearrange the sentence structure in a way that does not correctly address the shift in voice.