unless my math is wrong... (D) can still be argued to be the right answer because if a bunch of people move into town, regardless of their age, there has to be an increase of 65+ for the average to increase anyway. say there was 52 seniors/100 townspeople last year (52%) and this year there's 114 seniors/200 townspeople. As the number of townspeople increase, the number of seniors must increase to justify the 57% or vice versa. same logic as (A). Somebody please help!