Final answer:
MiniITX is the subject that has a maximum size of 6.7 inches by 6.7 inches and is used in small-sized computers.
Step-by-step explanation:
The subject you are referring to that has a maximum size of 6.7 inches by 6.7 inches is MiniITX. MiniITX is a small form factor motherboard that is commonly used in small-sized computers for applications such as home theater PCs and small-scale servers. It is smaller than MiniATX, which has a maximum size of 11.2 inches by 8.2 inches.
MiniITX boards are popular among those who want to build compact and energy-efficient systems. Its small size allows it to fit into tight spaces, while still offering a range of features and capabilities found in larger motherboards.
So, in summary, the subject you are referring to that has a maximum size of 6.7 inches by 6.7 inches is MiniITX, option B.
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