If Kamal's eighth birthday was celebrated $2$ years before then it means Kamal’s current age is $10$ years,
After $10$ years, Kamal’s age would be $10+10 = 20$ years, and father’s age will be twice this,
Father’s age after $10$ years will be $2\times 20 = 40$ years.
Father’s current age is $40-10 = 30$ years,
Ashok’s present age is $\frac{1}{6} \times 30 = 5$ years.
Option D is correct.