Nhận biết (M1)

For the past 20 million years, Earth's magnetic poles in the far

north and far south have remained roughly where they are today.

This has not always been the __________ throughout geologic

history, Earth's magnetic poles have swapped places several times

through a process called polar wandering.

Which choice completes the text so that it conforms to the

conventions of Standard English?

• A.

  case; though,

• B.

  case, though.

• C.

  case, though;

• D.

  case, though