The option C correctly ranks the alkenes in order of decreasing stability, starting with the most stable on the left and least stable on the right:
C > A > B > D .Therefore, option C C > A > B > D is correct.
Alkenes are most stable when they are more substituted, meaning that they have more alkyl groups attached to the carbon atoms that are double bonded to each other.
Alkyl groups are electron-donating groups, which help to stabilize the alkene by reducing the partial positive charge on the carbon atoms in the double bond.
In the image you provided, alkene C is the most substituted, with two alkyl groups attached to each carbon atom in the double bond.
Alkene A is less substituted, with one alkyl group attached to each carbon atom in the double bond.
Alkene B is even less substituted, with only one alkyl group attached to one of the carbon atoms in the double bond.
Alkene D is the least substituted, with no alkyl groups attached to either of the carbon atoms in the double bond.
Therefore, the order of decreasing stability of the alkenes in the image is:
C > A > B > D