In which country is milk transported from farms to factories through pipelines?

The correct option is Canada.

Detailed Explanation:
Pipelines are a highly efficient mode of transport used for carrying liquids and gases over long distances without interruption. While pipelines are globally known for transporting water, crude oil, and natural gas, their application has been extended to other liquid materials in specific regions.
In Canada, a unique application of this transport system exists where milk is transported directly from dairy farms to processing factories through specialized pipelines. This system offers several advantages:
1. Quality and Hygiene Control: Closed pipeline systems minimize exposure to external environmental factors, ensuring that the milk remains uncontaminated, fresh, and cold during transit.
2. Efficiency: Continuous flow through pipelines reduces the need for manual handling, loading, and unloading associated with road transport (like tankers).
3. Cost-Effectiveness: For high-density dairy farming regions, direct pipeline connections significantly lower transportation and logistics costs over time.