Which of the following statements best describes the Biba security model?

A. No read up and write up
B. No write up and no write down
C. No read up and no write down
D. No read down and no write up

Answer: D
Explanation: The Biba model objective is to ensure data integrity. The model works on the principle of restricting users to read data at lower than their level and to write data at higher than their security level. This model was designed in the 1970s for the U.S. military.