About 200 million years before all the continents were part of one vast land mass called Pangea54/79Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction. About 200 million years before all the continents were part of one vast land mass called Pangea.millionbeforepartone vast land massGiải thíchĐáp án là B. before => ago