Which of the following satellites is the example of those orbiting in equatorial plane of the earth?

Correct option is C

KALPANA-1 is a geostationary satellite, which orbits the Earth in the equatorial plane at an altitude of approximately 36,000 km.
Being in this orbit, it matches the Earth’s rotation and appears stationary over a fixed point on the equator.
It was primarily used for meteorological observations.
Explanation:
(a) SARAL – A satellite in sun-synchronous orbit, not equatorial.
(b) RISAT-1 – An earth observation radar satellite in polar sun-synchronous orbit.
(c) KALPANA-1 – Correct answer. A geostationary satellite orbiting in the equatorial plane.
(d) IRS-1A – First Indian remote sensing satellite, placed in sun-synchronous polar orbit, not equatorial.