What is software that, while purporting to serve some useful function and often fulfilling that function, also allows Internet advertisers to display advertisements without the consent of the computer user?

Adware is the correct answer to the given question.

Explanation:

Adware is a type of software that turns a profit for its creator by creating online advertising in the software's user interface automatically. The Adware  giving the advertisement in the website or in the web page. There are two different ways in which Adware is going on the computer  

1 Malicious website    

2 Shareware.

Adware software is used to purporting to serve some useful function adware software display the advertisements without the consent of the computer user or machine.

idk rn, probably a tie between apex and fortnite, but outside those four, my fav game is 2k

explanation:

he could use bold or bigger text just a suggestion.