Nhận biết (M1)

An emulsifier is a type of compound that serves to stabilize an emulsion—a mixture of two or more liquids that otherwise would not easily blend together. In the cosmetics industry, emulsifiers such as cetyl hydroxyethylcellulose __________ to blend oil and water into homogeneous formulations, like lotions and perfumes.

Which choice completes the text so that it conforms to the conventions of Standard English?

• A.

  are employed

• B.

  employed

• C.

  that they employ

• D.

  being employed