Upon activation of an interrupt, the microcontroller goes through some important steps, which are mentioned below. What will be the correct sequence of these steps (in ascending order) during execution?

Step A: Microcontroller saves the current status of all the interrupts internally (i.e., not on the stack) Step B: The microcontroller gets the address of the ISR from the interrupt vector table and jumps to it. It starts to execute the interrupt service subroutine unit it reaches the last instruction of the subroutine, which is RETI (return from interrupt). Step C: The microcontroller finishes the instruction it is executing and saves the address of the next instruction (PC) on the stack. Step D: Microcontroller jumps to a fixed location in memory called the interrupt vector table that holds the address of the interrupt service routine. Step E: Upon executing the RETI instruction, the microcontroller returns to the place where it was interrupted. First, it gets the program counter (PC) address from the stack by popping the top two bytes of the stack into the PC. Then it starts to execute from that address. Options:

1. C, B, D, A, E
2. C, A, D, E, B
3. B, C, D, A, E
4. C, A, D, B, E