Concept:Grazing systems describe how livestock are allowed to feed on pasture over time and space.
Explanation:In West Africa, most livestock are kept under traditional, low-input management.
Animals are allowed to roam and graze freely over natural pastures for long periods.
This practice is called continuous grazing.
Rotational grazing requires fencing animals into paddocks, which is not commonly practised on a large scale in West Africa.
Deferred grazing and zero grazing are also less common because they need more management or housing.
Therefore, the most common system is continuous grazing.
Answer:A. continuous grazing