Explanation:

- Option 1: AIIMS

- The All India Institute of Medical Sciences (AIIMS) is a group of autonomous public medical colleges of higher education.

- Known for providing tertiary healthcare services in India.

- Option 2: Post Graduate Institute

- Generally refers to the Postgraduate Institute of Medical Education and Research (PGIMER) in Chandigarh.

- It offers tertiary healthcare services and focuses on postgraduate education in medical sciences.

- Option 3: NIMHANS

- The National Institute of Mental Health and Neurosciences (NIMHANS) is an institute specifically focusing on mental health and neurosciences.

- It is recognized as a tertiary healthcare institution in India.

- Option 4: All of the above

- AIIMS, PGIMER, and NIMHANS are all tertiary healthcare institutes.

- They provide specialized and advanced medical care.

Correct Answer: Option 4 - All of the above