A Space Rocket Is Launched Such That Very Far from Earth

Multiple Choice

A space rocket is launched such that very far from Earth it has a speed of 20 km/s.What was its initial launch speed from the surface of Earth? (R_E = 6.38 $\times$ 10⁶ m,M_E = 5.98 $\times$ 10²⁴ kg,G = 6.67 $\times$ 10^-11 N·m²/kg²)

A) 22.9 km/s
B) 20.0 km/s
C) 45.8 km/s
D) 21.5 km/s
E) 25.5 km/s