Here, reaction 1 will be the most favourable product formation.
is an anion with a resonance stabilization. Due to the -I effect of the ketone group, the electron density on O will decrease and there will be an electron delocalisation as well as increases its stability.

The product formed in reaction 3 iswhich has fulfilled octet. But the stability of primary amine is not that much of secondary, tertiary amine or carboxylate ion as it will have only one group to increase its electron density.
Reaction 2 and 4 both are unstable as there is no such resonance stability or no group having -I effect to decrease the electron density.
So, formation of carboxylate ions is the most stable one.