Option 1 -> States Chandrayaan-4 is unrelated to ShakthiSAT, but the passage explicitly says ShakthiSAT "will be part of ISRO's Chandrayaan-4 mission in 2026."
Option 2 -> Suggests it will carry a woman astronaut, but the passage describes a satellite mission, not a crewed mission.
Option 3 -> Correctly identifies that Chandrayaan-4 will be the mission carrying the ShaktiSAT spacecraft to lunar orbit.
Option 4 -> While technically accurate, it doesn't directly address the relationship; it describes what will happen rather than the significance of the connection.
Hence, Option 3 -> The passage clearly states that Mission ShakthiSAT "will be part of ISRO's Chandrayaan-4 mission in 2026," making Chandrayaan-4 the launch vehicle/mission that will carry the student-built ShaktiSAT spacecraft on its journey from lunar-to-lunar orbit. This represents the primary significance of the relationship between the two missions. -> correct