it should be b because she researched before writing so it would be in past tense. "the author researches her subject before she had written the first draft.
Answer from: Quest
the answer is
Another question on English
English, 21.06.2019 21:00
What is the name of the built-in photo editor program on windows
No commitments. Cancel anytime. All pricing is in US dollars (USD). The subscriptoin renews automaticaly until you cancel. For more information read our Terms of use & Privacy Policy