Explanation:

- Correct Answer: Option 2 - Boeing 737 Max 8

- In March 2019, the DGCA of India grounded the Boeing 737 Max 8 aircraft following two major crashes involving this model, Lion Air Flight 610 in October 2018 and Ethiopian Airlines Flight 302 in March 2019. These incidents raised concerns about the aircraft's safety, specifically related to its Maneuvering Characteristics Augmentation System (MCAS).

- Option 1 - Boeing 787 Max 14

- The Boeing 787 is known as the Dreamliner, not associated with the "Max" series, and has not been grounded due to similar issues.

- Option 3 - Boeing 777 Max 12

- The Boeing 777 series does not include a "Max" variant. The 777 is unrelated to the issues faced by the 737 Max series.

- Option 4 - Boeing 747 Max 9

- The Boeing 747 is a separate model line with no "Max" variant, primarily serving as a long-haul, wide-body aircraft, unaffected by the grounding of the 737 Max series.