He was trying to delete import data on the computer and "was burning/(to) burn" some documents.
a. When the police broke into the house, he was trying to delete important data on the computer and "was burning" some documents.
b. When the police broke into the house, he was trying to delete important data on the computer and “burn” some documents.
c. When the police broke into the house, he was trying to delete important data on the computer and “to burn” some documents.
→Which sentence is correct? Which makes more sense? Between sentences b and c, do you tend to omit "to" or not?
Thanks!