Primary colours are the basic colours that cannot be made by mixing other colours.
In the subtractive colour model (used in painting and pigments), the primary colours are: Red, Yellow, and Blue.
All other colours can be formed by mixing these in various combinations.
\begin{itemize}
\item Option (B) includes Black and Green, which are not primary.
\item Option (C) includes Green and Black again — incorrect.
\item Option (D) is eliminated as option (A) is valid.
\end{itemize}
\[
\boxed{\text{Primary Colours = Red, Yellow, Blue}}
\]