Option D is the answer because having computer network on computers does not help to avoid spyware, there are other software that help us to avoid spyware for example Norton spyware which does not come with computer networks.
It helps in installing computer applications like OS updates are installed because of it so option A is actually is a benefit.
As the computer OS is updated by the networks so it actually helps you to install the desired OS, the best example is when people update windows 10 from windows 7, so Option B is also an actual benefit.
Yes, many software are licensed when you buy a OS so option C is also an actual benefit.