Ganesh went to the office at the speed of 60 km/hr while returning to his home he covered the half of the distance at the speed of 10 km/hr, but suddenly he realized that he was getting late, so he increased the speed and reached the home by covering rest half of the distance at the speed of 30 km/hr. The average speed of the Ganesh in the whole length of journey is:
A)5.67 km/hr B)24 km/hr C)22.88 km/hr D)5.45 km/hr