After the Battle of Smolensk Emperor Alexander I had to choose a new general and he 2 Kutuzov.

1. The context implies a selection or decision process. 'CHOOSE' is provided as an option.
2. The sentence requires a past participle to complete the passive construction 'had to choose a new general and he was ...'. However, the sentence structure suggests a direct object for 'choose', implying Alexander chose Kutuzov.
3. The word 'CHOOSE' is transformed into 'chose' to fit the past tense and the active voice of Alexander's action.
Final Answer:

chose