Step 1: Role of Chief Election Commissioner (CEC)
- The CEC is the head of the Election Commission of India, responsible for conducting free and fair elections.
Step 2: Appointment process
- According to the Constitution of India, the CEC is appointed by the \textit{President of India}.
- The appointment is made independently and not influenced by the Council of Ministers or Parliament.
Step 3: Why other options are incorrect
- (A) Council of Ministers does not appoint the CEC.
- (B) Prime Minister does not appoint the CEC directly.
- (C) Parliament does not appoint the CEC.
Therefore, option (D) is correct.