Which sentence uses active voice to emphasize the actor in an academic argument?

• A. The experiment was conducted by the researchers to test the hypothesis.
• B. The researchers conducted the experiment to test the hypothesis.
• C. Conducting the researchers the experiment tested the hypothesis.
• D. The hypothesis tested the researchers' experiment.

Answer: (B)

Active voice foregrounds who performs the action, which is exactly what you want when you need to emphasize the actor in an academic argument. The sentence The researchers conducted the experiment to test the hypothesis keeps the actor—The researchers—at the very start, with the action conducted immediately after them and the object receiving the action— the experiment. The purpose phrase to test the hypothesis explains why the action happened, but it doesn’t shift focus away from who did it. This direct subject–verb–object order makes the researchers the clear center of the claim, which is why it’s the best choice for emphasizing the actor.

Shifting to a passive construction—The experiment was conducted by the researchers to test the hypothesis—puts the experiment first, so the actor becomes secondary. One of the other options is not grammatical as written and would be awkward or confusing, and another would flip the meaning so that the hypothesis appears to do the testing, which misplaces who is performing the action.