Satellites used for telecommunication relay are kept in a geostationary orbit. A satellite is said to be in such an orbit when:
1. The orbit is geosynchronous.
2. The orbit is circular.
3. The orbit lies in the plane of the Earth’s equator.
4. The orbit is at an altitude of 22,236 km.
Select the correct answer using the codes given below: [UPSC 2011 (CS-P)]

1, 2 and 3 only
1, 3 and 4 only
2 and 4 only
1, 2, 3 and 4