Answer: fetch-decode-execute
Step-by-step explanation:
When a CPU needs to execute an instruction, it must first fetch what that instruction is to prepare the proper registers and flags for use, then it needs to decode the data to know where to manage the data needed for the instruction in the registers and on the stack, and then finally it can execute the instruction. Not mentioned here is what to do after would be to store that resulting information back into memory.
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