Problem Hiroki and Mapiya were asked to find an explicit formula for the sequence 125\,,\,25\,,\,5\,,\,1,...125,25,5, 1,...125, comma, 25, comma, 5, comma, 1, comma, point, point, point, where the first term should be f(1)f(1)f, left parenthesis, 1, right parenthesis. Hiroki said the formula is f(n)=625\cdot\left(\dfrac{1}{5}\rig ht)^{{n}}f(n)=625⋅( 5 1 ​ ) n f, left parenthesis, n, right parenthesis, equals, 625, dot, left parenthesis, start fraction, 1, divided by, 5, end fraction, right parenthesis, start superscript, n, end superscript, and Mapiya said the formula is f(n)=125\cdot\left(\dfrac{1}{5}\rig ht)^{{n}}f(n)=125⋅( 5 1 ​ ) n f, left parenthesis, n, right parenthesis, equals, 125, dot, left parenthesis, start fraction, 1, divided by, 5, end fraction, right parenthesis, start superscript, n, end superscript. Which one of them is right? Choose 1 Choose 1 (Choice A) A Only Hiroki (Choice B) B Only Mapiya (Choice C) C Both Hiroki and Mapiya (Choice D) D Neither Hiroki nor Mapiya