Question #N1067
The most recent discovery by scientists about the planet Mars has been met with much excitement. The research team, led by Dr. Emily Carter, has been studying the planet's atmosphere and looking for signs of past life. Dr. Carter and her colleagues have found evidence of methane, a gas that is a key indicator of life. This discovery, which is expected to be published soon, has implications for our understanding of the planet, and the possibility of life beyond Earth.
Which choice best revises the underlined portion of the sentence to create a grammatically correct and clear sentence?
A. This discovery which is expected to be published soon,
B. This discovery, expected to be published soon,
C. This discovery, which is expected to be published soon,
D. This discovery, expected to be published soon,
Correct Answer is: B
The underlined portion of the sentence is a nonrestrictive clause because it is not essential to the meaning of the sentence. Therefore, it should be set off with commas. Choice B is the only choice that correctly sets off the clause with commas.