Over the given three years which has been the highest selling colour; and what percentage of volume did it account for?

Sales of red colour refrigerator in all the given years in thousands = (20 + 30 + 45) = 95

Sales of Blue colour refrigerator in all the given years in thousands = (25 + 32 + 48) = 105

Sales of Lemon colour refrigerator in all the given years in thousands = (47 + 23 + 32) = 102

Sales of Grey colour refrigerator in all the given years in thousands = (2 + 27 + 34) = 63

Sales of White colour refrigerator in all the given years in thousands = (32 + 45 + 43) = 120

Highest selling colour is white. Percentage of volume it accounted for, is given by,

Required percentage = $$\frac{120}{95 + 105 + 102 + 63 + 120} \times 100$$

= $$\frac{12000}{485} = 25$$% (approx)

Hence, option B is the correct answer.