A provider keeps copies of their client records on an external hard drive, just in case something happens to his primary office computer. Under HIPAA, what is the best way for the provider to store the external hard drive?
a. In an unlocked drawer within the office for quick access.

b. In a locked cabinet within the office.

c. At the provider's home for personal convenience.

d. In a secure off-site location, such as a safe or a data storage facility.