The outputs (Q0-Q3) of the memory are always LOW. The address lines (A0-A7) are checked with a logic probe and all areindicating pulse activity, except for A3 which shows a constantHIGH, and A7 which shows a constant LOW; the select lines, S0 andS1 are checked and S0 shows pulse activity, while S1 indicates aconstant HIGH. What is wrong, and how can the memory be tested to determine whether it is defective or if the external circuitry is defective?