A nested function calls another function $($plot$\_$function with parameter $a0)$ and is also called

by another function. Given the code that follows RISCV calling convention, which sets of

registers should be saved to make this program run more optimally. All the function knows

is that the plot$\_$function uses $aO$ as a parameter, and its own caller passes a value in a$0.$ mv

s$1,$ s$2$ is the pseudo instruction equivalent of: addi s$1,$ s$2,0$

What combinations should apply $($mark as all that are true$)$: