Final answer:
Sena should know that banks may require collateral or a cosigner for loans, in addition to conducting a credit check to assess credit history before approving a loan.
Step-by-step explanation:
When Sena is considering applying for a loan at a bank, she should be aware of various important aspects of banks and credit. Banks typically require potential borrowers to submit forms detailing their income sources and they also conduct a credit check to examine past borrowing and credit history.
Additionally, banks may require a cosigner, someone who agrees to repay the loan if the original borrower fails to do so. A common requirement is for collateral, such as property or equipment, which the bank can seize and sell if the loan is not repaid. This information helps Sena to understand that the correct statement from the options provided is 'b. they may require some form of security for loans.'