下面哪一个字符串变量定义语句是不正确的？

下面哪一个字符串变量定义语句是不正确的？
A.var mytext = "Here is some text!"
B.var mytext = 'Here is some text!'
C.var mytext = 'Here is some text!"
D.var mytext = "Here is\nsome text!"
正确答案：C