Select the option that expresses the given sentence in active voice.

Four grams of sodium chloride was added to the mixture by the research team.

The research team added four grams of sodium chloride to the mixture

The correct option that expresses the given sentence in active voice is The research team added four grams of sodium chloride to the mixture.

The other options are incorrect because:

• Four grams of sodium chloride was added to the mixture by the research team is in the passive voice.
• The research team added the mixture to four grams of sodium chloride is in the active voice, but it does not emphasize the action of adding the sodium chloride.
• Four grams of sodium chloride added the mixture to the research team is grammatically incorrect. The subject of the sentence is "four grams of sodium chloride," which is not a person. Therefore, the verb "added" cannot be used in the active voice.
• The mixture added four grams of sodium chloride to the research team is grammatically incorrect. The subject of the sentence is "the mixture," which is not a person. Therefore, the verb "added" cannot be used in the active voice.