Step 1: Recall the Nearest Neighbour method.
The Nearest Neighbour method assigns the value of the closest sample to the estimation block without smoothing or interpolation.
Step 2: Identify its application.
Since it assumes a random distribution of samples and produces abrupt changes between adjacent blocks, it is generally used only for preliminary or rough resource estimates.
Hence,
\[
\boxed{\text{Nearest Neighbour method}}
\]
is the correct answer.
Therefore,
\[
\boxed{(D)}
\]
is the correct answer.