Which Is True of a Local Interpolation Method

Which is true of a local interpolation method?

A) All points in the dataset are used to determine an unknown value at a particular location.
B) A subset of both the closest known points to a location as well as a subset of the farthest away known points from a location are used in the interpolation process.
C) Only the values of the three closest known points are used to determine the unknown value for a location.
D) A small subset of known points near a location are used to determine the unknown value at that location.