Choose the correct statement:

a$.$ Aside from the processor, the most important chip on the motherboard is the BIOS chip.

b$.$ There are a few different hard drive standard connectors. The newer and much faster one is Parallel ATA $($PATA$).$

c$.$ If your system runs low on RAM, it can use ROM as an alternative.

d$.$ There are seven different speeds supported by PCIe. $\backslash$times $12$ is the most common.