Let the function f(x) = 2x3 + (2p – 7)x2 + 3(2p – 9)x – 6 have a maxima for some value of x < 0 and a minima for some value of x > 0. Then, the set of all values of p is
a. (9/2, [infinity])
b. (0,9/2)
c. (-[infinity],9/2)
d. -9/2,9/2)