There are some websites that are trustworthy. For instance just beside the address bar there will be a lock. You can scroll over it with your mouse to see if it states that it is a secure connection.
Virus protection if accountable should also advise whether website is safe or not.
Always scroll down to the bottom of the page and check their security sites, as in McAfee, Norton, Etc.
The answer is D: Read the website thoroughly!!!!
Always be skeptical and reluctant, as technology advances, so do hackers and online criminals. People are far too brave and crazy these days.
Most bank accounts offer some type of an additional account you can use for online transactions. For instance you may have a checking that you have to pay your bills with (keep your bill money, etc in the account not being used online). Then they may offer another type of account, my bank refers it to an eaccess account, This is where I can use their online app to transfer money, through my bank app, for online purchases only. Therefore if someone has my account information they aren't getting access to my money that is an absolute necessity, just the little online purchase at a time one, that is also FDIC insured and after a dispute you will be reimbursed in due time.
Another option is PayPal, Paypal actually has a cash debit card now that makes life so much easier when paying. Using paypal pay they only have access to a prepaid debit card.