According to the Serra text, what does the cloud service model Infrastructure as a Service $($IaaS$)$ primarily offer?

Question $1$ options:

Fully managed software and applications.$$ You are essentially renting a software engineer.

Pre$-$built platforms for application development.$$ You are renting a hard drive with programs like Python pre$-$installed.

SaaS $($software as a service$)$ for a monthly subscription fee.$$ Salesforce.com is a good example of this.

Virtualized computing resources such as servers and storage.$$ You are in essence renting space on somebody else's computer.

None of these.