Which statement is wrong about the sounds /i:/ and /ɪ/?（ ）
选项：

A:/i:/ is much more tense sound than /ɪ/.
B:The /ɪ/ sound is made by lowering the tongue slightly from the position for /i:/.
C:The difference in length is the only difference between them.
D:They are produced in the front of the mouth.