The correct answer is B.
For SDR SDRAM, the number after the “PC” component of the names refers to the clock frequency for which the memory modules are rated. Chips that are rated for slightly higher than the modules are routinely used so that they are not working at maximum capacity at all times. As a result, PC100 modules would use slightly faster 125 MHz chips. The values 125 MHz and 8 ns are reciprocals of one another (divide 125 million into 1 to get 8 billionths and vice versa).
A+ Certification Prep Course