Risk$-$Free Rate. What is a risk$-$free rate? Give an example of an investment with a risk free rate. Why is there no risk?

A risk$-$free rate is: $($Select the best answer below.$)$

A$.$ an interest rate that is not guaranteed on an investment for a specified period.

B$.$ an interest rate guaranteed on an investment for a unspecified period.

C$.$ an interest rate guaranteed on an investment for a specified period.

D$.$ an interest rate that is not guaranteed on an investment for an unspecified period.

There is no risk because a risk$-$free investment: $($Select the best answer below.$)$

A$.$ pays an interest rate guaranteed on an investment for an unspecified period.

B$.$ would pay investors even if the financial institution went into bankruptcy.

C$.$ is a checking account.

D$.$ is a zero interest loan.