Which Description of the Famous Tongue Map from Boring (1942)

Which description of the famous tongue map from Boring (1942) is correct?

A) Sweet is only tasted on the top front of the tongue.
B) Salt is only tasted on the front tip of the tongue.
C) Bitter is only tasted on the back of the tongue.
D) Sour is only tasted on the sides of the tongue.
E) None of these are correct and the tongue map is false.