Select the option that expresses the given sentence in passive voice.
Scientists were conducting experiments on the newly discovered species.

Correct option is D

The correct passive voice of the given sentence is  (d) "Experiments were being conducted on the newly discovered species by scientists."
Explanation:
Active Voice:
· Subject: Scientists
· Verb: were conducting
· Object: experiments on the newly discovered species
Passive Voice Rule:
· Structure: Object + was/were + being + past participle + by + subject
· Conversion:  Experiments (object) +  were being +  conducted +  by scientists.
Example: The team was repairing the machine → The machine was being repaired by the team.