Nhận biết (M1)

The Kaiparowits Formation is a fossil-rich layer of sedimentary rock in the Grand Staircase, a colossal sequence of rock layers stretching from Utah’s Bryce Canyon to Arizona’s Grand Canyon. The sandstones and mudstones of the Kaiparowits Formation were deposited __________ the Late Cretaceous, preserving many species from that time.

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

• A.

  during;

• B.

  during:

• C.

  during

• D.

  during,