Which of the following would be an implementation of a function
named: mystery\_one, which takes the value of x in register r0 and
value of y in register r1, computes $r = 4*(x+y)$, and returns r in r0?
mystery\_one:
add r0, r1
mov r0, r0, asl \#4
mov pc, lr
mystery\_one:
add r0, r1
mov r0, r0, asr \#2
mov pc, lr
mystery\_one:
add r0, r1
add r0, r0, asl \#2
mov pc, lr
mystery\_one:
add r0, r1
add r0, r0, asr \#2
mov pc, lr
None of the above