An arrow is shot so that it hits the target above. which of the following describes the method for calculating the probability of hitting the red region?
a. area of white circle/ (area of blue circle - area of yellow circle)
b. (area of blue circle - area of yellow circle) / area of white circle
c. area of white circle / (area of red circle - area of yellow circle)
d. (area of red circle - area of yellow circle) / area of white circle