Concept:Build an equation from Tom's future age and the age difference with Bade.Explanation:Let Tom's present age be x years.Since Tom will be 25 years old after n years, we have:x+n=25So Tom's present age is:x=25−nTom is 5 years younger than Bade.Therefore, Bade's present age = Tom's present age + 5.Bade's present age = (25−n)+5Bade's present age = 30−n years.Answer:Bade's present age is (30−n) years, which is option A.