ISRO's ambitious interplanetary mission, 'Shukrayaan-1', successfully entered the orbit of Venus in late 2026. What is the primary scientific objective of this mission?

1. ATo search for evidence of past microbial life in the Jezero crater.
2. BTo deploy a rover to study the composition of the lunar south pole.
3. CTo study the composition of the Venusian atmosphere and its runaway greenhouse effect using an orbiter.
4. DTo establish a communication relay satellite for a future Mars mission.