A security self$-$assessment revealed that Penelope, who owns one laptop computer, is putting herself at risk for cyberattack by

a$.$ avoiding signing in to her

Amazon.com account while using free wifi at the coffee shop

b$.$ backing up critical files to a single folder on her laptop once every three months

c$.$ deleting emails from people or businesses unfamiliar to her

d$.$ refraining from clicking on URLs in the bodies of email messages