The following statement are associated with the occurrence of notochord. Identify the incorrect statement.

A. It is present only in larval tail in ascidians.

B. It is replaced by a vertebral column in adult frog.

C. It is absent throughout the life in humans from the very beginning.

D. It is present throughout life in Amphioxus.

Please do not use chat terms. Example: avoid using "grt" instead of "great".