What are the different options for controlling gastrointestinal nematodes in sheep without the use of drugs?

The manipulation of pastures can be done to reduce the risk of infection, such as resting pastures to have safe or clean pastures.
Animal management strategies can be used to minimize pasture contamination with larvae.
The use of drugs is the only effective way to control gastrointestinal nematodes in sheep.
The Control Integrado de Parásitos (CIP) is a technique that requires the availability of techniques for the diagnosis of drug resistance, a verification of the quality of anthelmintics, and knowledge of local parasite epidemiology.
a) I and II are correct.
b) II and IV are correct.
c) III and IV are correct.
d) I and III are correct.