The Mac Pro (Early 2009) has SMC functionality split between a primary SMC on the backplane board, and a secondary SMC on the processor board. What service
issue should a technician be aware of when servicing the Mac Pro (Early 2009)?

A.
SMC firmware must always match on both boards.

B.
Three internal buttons must be pressed in order to reset both SMCs.

C.
It is required to remove the memory riser card in order to reset the SMC.

D.
Processor trays are interchangeable between similar Mac Pro (Early 2009) units.