To calculate geometry over an Earth-like sphere, store your location data on a spherical surface and use _____ index.

To calculate geometry over an Earth-like sphere, store your location d

1.	To calculate geometry over an Earth-like sphere, store your location data on a spherical surface and use _____ index.
A.	2dsphere
B.	2d
C.	geoHaystack
D.	all of the mentioned
Answer» B. 2d