Break the phrase into its history to understand it. "Stave" originally meant to fend off a blow with a staff or stick, and "off" adds the sense of pushing something away. Together, "stave off" means to hold back a bad outcome for some time.
Now test each option against the sentence: "The company managed to ___ bankruptcy for another few months." Only "delay something bad" makes sense with "for another few months", because that phrase signals a temporary postponement, not a permanent fix.
"Cancel" would not need the time phrase "for another few months", since a cancelled event does not return later. "Implement instantly" and "follow" do not connect to bankruptcy being avoided at all.
So the meaning of "stave off" is confirmed as option A, "To delay something bad".