Concept:Cassava is suited to the last position in a crop rotation because it can grow well even when the soil has lost most of its fertility.
Explanation:In a crop rotation system, crops are arranged in an order that makes the best use of the soil.
Cassava is a deep rooted crop.
Its roots extend far into the subsoil to take up water and nutrients.
By the time cassava is planted, the topsoil may already be depleted of nutrients.
Shallow rooted crops would perform poorly in such exhausted soil.
Cassava, however, can still produce a reasonable yield on nutrient-depleted soils.
This is why farmers prefer to place cassava at the end of the rotation.
Answer:The correct option is C: cassava comes last in the rotation because it is a deep rooted crop.