Relative stability of the contributing structures is :

Solution

Chemistry ma’am · 3 steps

Neutral beats charge-separated, and a minus charge belongs on oxygen, never a plus.

1. Rules to apply. A neutral structure with every octet complete is the most stable. Among charge-separated structures, the better one has the negative charge on the more electronegative atom.

   Structure	Charges	Octets	Verdict
   (I)	none	all complete	most stable
   (II)	- on O, + on CH₂	terminal C has only 6	middle: charge separated, but the minus sits on electronegative O
   (III)	+ on O, - on CH₂	O has only 6	least stable: plus on O and minus on C are both wrong

2. Compare II and III. Both separate charges and both leave one atom with 6 electrons. (II) puts the negative charge on oxygen, which holds it well. (III) puts the positive charge on oxygen and leaves oxygen electron-deficient, which is very unfavourable.
3. So. The order is (I) > (II) > (III), option (d).

The idea to keep. Rank resonance structures in this order of checks: no charge separation first, then complete octets, then negative charge on the more electronegative atom.

Answer from the NTA final answer key. Solution by PrepWiser.