which of the following shows correct arrow placement that represents significant resonance for the given…

Brief Explanations:

Resonance involves the delocalization of electrons. For a carbon - oxygen double - bond ($C = O$), significant resonance occurs when electrons from the pi - bond can be delocalized. The correct arrow placement for resonance in a carbonyl compound is when the pi - electrons of the $C = O$ bond move towards the oxygen atom (which is electronegative), creating a negative charge on oxygen and a positive charge on the adjacent carbon. In the given options, the arrow should start from the pi - bond of the $C = O$ and point towards the oxygen atom.

Answer:

The arrow starting from the $C = O$ pi - bond and pointing towards the oxygen atom (the last option in the list where the arrow is from the double - bond to the oxygen) represents significant resonance.