In option A, the article should be” a” instead of” an”, and in option D, the article” an” is incorrectly used before” unique,” as ”unique” begins with a ”y” sound, requiring "a.”
Arun’s present age in years is 40% of Barun’s. In another few years, Arun’s age will be half of Barun’s. By what percentage will Barun’s age increase during this period?