Which of the following is the correct formula for distance? (A.) d= (x2-x1)^2+(y2-y1)^2, where d is the distance between points (x1,y1) and (x2,y2).
(B.) d= sqrt (x2+x1)^2+(y2+y1)^2, where d is the distance between points (x1,y1) and (x2,y2).
(C.) d= sqrt (x2-x1)^2+(y2-y1)^2, where d is the distance between points (x1,y1) and (x2,y2).
(D.) d= sqrt (x2-x1)+(y2-y1), where d is the distance between points (x1,y1) and (x2,y2).