Answer:
Option A is correct.
Step-by-step explanation:
He attaches the second 1 Gigabyte 240 pins DIMM for his system the overall RAM will be up around 2 Gigabytes. System is fitted with Intel Core 2 Dual 3-GHz cpu as well as three 240 pins DIMM ports on the motherboard. Transforms on a system, just 1 Gigabytes of RAM is seen through that RAM count.
Thus, the following issue is much more probably to be the failure to correctly grab that RAM.