Which of these options is not recommended?

a$.$

Read all spam emails before deleting them.

b$.$

If you are using a public workstation, you can save your files on the computer if you've used that particular computer before.

c$.$

Before entering your information on a website, look for the lock icon to confirm that the website is secure$.$

d$.$

Install commercially available antivirus software instead of free options that are installed by default on your computer.