Correct option is D
The satellite IRNSS-1H was the only one from the Indian Regional Navigation Satellite System (IRNSS) series that failed to launch successfully. The IRNSS-1H was supposed to replace IRNSS-1A after its atomic clocks stopped functioning. However, during the launch on 31st August 2017, a technical glitch occurred when the heat shield of the PSLV-C39 launcher did not separate, preventing the satellite from reaching its intended orbit. This incident marked a rare failure for the highly reliable Polar Satellite Launch Vehicle (PSLV) of ISRO. The IRNSS program, also known as NavIC (Navigation with Indian Constellation), aims to provide accurate positioning services over India and the surrounding region, similar to GPS. Despite the failure of IRNSS-1H, the NavIC system remains operational, supported by other functioning satellites in the series.
