In "mother tongue," how does amy tan demonstrate language bias toward her mother?
a: she believed her mother's thoughts were unimportant because she expressed them imperfectly.
b: she refused to go out with her mother in public because she was ashamed of her accent.
c: she only spoke perfect standard english with her mother in an attempt to make her mother speak more clearly.
d: she would not impersonate her mother on the phone when making important calls for her.