选项
A.
A.There have been two assumptions as far as the evolution of languages is concerned.
B.
B.All languages have evolved from a single one and was used in their ancient times.
C.
C.There were large number of languages earlier and then they got integrated into fewer ones that we know now.
D.
D.All languages have evolved from more than a single one and was used in their ancient times.
正确答案：