Step 1: Understanding primary activities.
- Primary activities are those which are directly connected with the utilization of natural resources.
- Examples include agriculture, fishing, forestry, hunting, and mining.
Step 2: Check each option.
- (A) Agriculture → Directly uses land and natural resources → Primary activity.
- (B) Hunting → Direct exploitation of animals in nature → Primary activity.
- (C) Mining → Extraction of minerals from the earth → Primary activity.
- (D) Manufacturing → Involves processing of raw materials into finished products in factories → Secondary activity.
\[
\boxed{\text{Manufacturing is not a primary activity; it is a secondary activity.}}
\]