Answer:
First option i.e., Multicore processors usually run older software by using only one core at a time.
Explanation:
Multicore processors performing earlier software composed against particular memory chips which would be Multicore processor typically perform earlier apps only by single core at the same period are facing the following issue.
It is the core that has connected double or even more processors for increasing its work, minimal energy usage and much more robust combined execution of multitasking