Explanation:

- Option 1: March 2016

- The National Common Mobility Card (NCMC) project wasn't launched this year. Other developments in payment systems might have occurred, but not the NCMC.

- Option 2: March 2018

- Some groundwork and planning for the NCMC were ongoing during this time, yet the official launch did not happen in 2018.

- Option 3: March 2019

- This is when India's first indigenously developed payment ecosystem for transport based on NCMC standards was launched.

- It aimed to facilitate seamless travel across different forms of transport within the country.

- Option 4: March 2017

- By this period, discussions about enhancing mobility payments were happening but the official launch was yet to come.