Find the local and global extrema for the polynomial function f in the given graph.
a. the local maximum is 98 at x = -1. the local minimum is -160 at x = 7. there is no global maximum or minimum.
b. the local and global maximum is 98 at x = -1. the local minimum is - 160 at x = 7. there is no global minimum.
c. the local maximum is -1 at x = 98. the local minimum is 7 at x = -160. there is no global maximum or minimum.
d. the local and global maximum is 98 at x = -1. the local and global minimum is -160 at x = 7.