sprang

[grandh01]

The voluminous personal papers of Thomas Alva Edison reveal that his inventions
typically sprang to life not in a flash of inspiration but evolved slowly from previous
works.
(A) sprang to life not in a flash of inspiration but evolved slowly
(B) sprang to life not in a flash of inspiration but were slowly evolved
(C) did not spring to life in a flash of inspiration but evolved slowly
(D) did not spring to life in a flash of inspiration but had slowly evolved
(E) did not spring to life in a flash of inspiration but they were slowly evolved.

[vk_vinayak]

The voluminous personal papers of Thomas Alva Edison reveal that his inventions
typically sprang to life not in a flash of inspiration but evolved slowly from previous
works.
(A) sprang to life not in a flash of inspiration but evolved slowly >> In the idiom 'not X but Y', X and Y should be parallel. Here that parallelism is violated.

(B) sprang to life not in a flash of inspiration but were slowly evolved >> Same as A.

(C) did not spring to life in a flash of inspiration but evolved slowly >> Correct. Maintains proper tense and parallelism.

(D) did not spring to life in a flash of inspiration but had slowly evolved >> No need to use past perfect.

(E) did not spring to life in a flash of inspiration but they were slowly evolved. >> Passive voice makes the sentence awkward. Repetition of the subject (they) is not needed.

Going Forward, please post the SC question with proper undelining.