DBI202Xuất hiện trong 1 đề thi
For what values of x, y, and z, including NULL, does the Boolean expression $x <= 100$ AND NOT($y >= 15$ OR $z = 35$) have the truth value UNKNOWN? Identify one of those values from the list below.
Các lựa chọn
A$x = \text{NULL}, y = 0, z = 4$.
B$x = -2, y = -2, z = -2$.
C$x = 3, y = 0, z = 7$.
D$x = 2, y = -1, z = 6$.