Which two $(2)$ statements about MIC$-1$ microcode are true?

Select one or more answers:

a$.$ The most significant instruction address bit $($MPC$)$ is only affected by the N and Z bits.

b$.$ The machine only jumps if the N or Z bit is $1.$

c$.$ The two jump targets for conditional jumps must be $256$ addresses apart.

d$.$ The machine jumps after each command.