问题：
[单选题]Which statement about narwhals is NOT true?
AThey are introverted sea mammals.
BThey are called “unicorn of the sea”.
CThey are rarely seen by people.
DThey will extinct if they get stressed.
[单选题]Which statement about narwhals is NOT true?
AThey are introverted sea mammals.
BThey are called “unicorn of the sea”.
CThey are rarely seen by people.
DThey will extinct if they get stressed.
