maryana noticed her computer is no longer as fast as it use to be when she purchased it a few months ago. she noticed that her computer is sluggish when she have several programs open. this is caused to her

random access memory

video card

motherboard

It is caused to her Random Access Memory RAM.

Explanation:

When a computer machine becomes slow on opening several programs this  signals to the problem than Random Access memory is lacking. It means an additional RAM is needed to speed up the process.

As not having enough RAM will make your hard drive to compensate hardly for the lacking memory. It is done by taking resources away from other program which result is slow speed of the system.

So Maryana's computer is short of RAM, she needs to add additional RAM or avoid accessing some unnecessary heavy programs.

I hope it will help you!