In which situation would a certificate of deposit (CD) be the best banking choice?

In which situation would a certificate of deposit (CD) be the best banking choice? Samuel is setting money aside but still needs emergency access to it. Hafsa wants a guaranteed return, and won’t need the money for several years. Darren is looking for an investment that has a very high interest rate. Raj is looking for an investment with a fast return so he can reinvest.