"X is Y" vs "X is like Y" vs "X is similar to Y"

See this question:

Q. Trying to mimic some of the pitch variations of a dolphin chattering is the same as attempting to sing like a sick parakeet when one is intoxicated; the complete lack of harmony and apparent randomness of the noise means the human vocal chords are completely incapable of reproducing these sounds.

A. the same as attempting to sing like a sick parakeet when one is intoxicated.
B. similar to an intoxicated person singing like a sick parakeet
C. like singing like a sick parakeet as an intoxicated person
D. the same as an intoxicated person singing like a sick parakeet
E. like the intoxicated person is singing like a sick parakeet

It involves parallel structure. You have to look carefully to figure out what form the comparison takes. The comparison is not one of similarity, it is on of equality. Saying "x is y" is quite different from saying "x is like y" or "x is similar to y". Choices B, C and E all change the fundamental underlying concept of the sentence. Choise D disrupts the parallel structure. The parallel structure is "trying to mimic" and "attempting to sing". A is the correct answer.