Concept:Regulatory control refers to official or legal measures enforced by authorities to restrict the movement of infected plants or materials and prevent the spread of crop diseases.
Explanation:The correct option is quarantine because it is a government-imposed restriction on the movement of plants, plant products, or agricultural goods from one area to another.
Quarantine helps prevent the introduction and spread of pests and diseases that can damage crops.
Rouging is the removal of infected plants from the field, which is a cultural control method.
Crop rotation is a farming practice where different crops are grown in sequence to break disease cycles, making it a cultural method.
Soil tillage is a physical or mechanical method used to prepare the land and destroy weeds or pests.
Since quarantine involves legal rules rather than physical or cultural practices, it is classified as a regulatory control.
Answer:B. quarantine