Consider a Boolean function f(w, x, y, z). Suppose exactly one input is…

Consider a Boolean function f(w, x, y, z). Suppose exactly one input is allowed to change at a time. If f is true for two input vectors i1 = (w1, x1, y1, z1) and i2 = (w2, x2, y2, z2), and i1 and i2 differ in exactly one bit position, we want f to remain true during the transition without becoming false momentarily. Let f(w, x, y, z) = ∑(5, 7, 11, 12, 13, 15). Which of the following cube covers of f ensures this required property?