Answer:
Spyware
Explanation:
The reason why you noticed your computer has been running slow is because of spyware, which is considered to be very bad to get on your computer. When a user opens his/her web browser, the user receives ads that are misleading to the user, which fools the user of thinking it's something real and not a scam. Not only that, the user also receives pop-up ads that can, as mentioned, trick the user to think that it's real and not fake. Finally, the user's search results will be manipulated. In conclusion, spyware is, in fact, the main cause of the scenario.