The correct order of reactivity in electrophilic substitution reaction of the following compounds is :

A species having carbon with sextet of electrons and can act as electrophile is called

Given below are two statements:

Statement I: IUPAC name of $$\mathrm{HO}-\mathrm{CH}_2-\left(\mathrm{CH}_2\right)_3-\mathrm{CH}_2-\mathrm{COCH}_3$$ is 7-hydroxyheptan-2-one.

Statement II: 2-oxoheptan-7-ol is the correct IUPAC name for above compound. In the light of the above statements, choose the most appropriate answer from the options given below:

The correct stability order of carbocations is