How do anticoagulant rodenticides kill rodents?

Anticoagulant rodenticides kill rodents primarily by preventing blood from clotting. These substances disrupt the normal clotting process by interfering with the synthesis of vitamin K, which is critical for producing clotting factors in the liver. When a rodent consumes an anticoagulant rodenticide, it leads to a decrease in the levels of these clotting factors, resulting in uncontrolled bleeding within the animal's body. This internal bleeding can be fatal, as it ultimately leads to shock and death due to the inability of the blood to coagulate properly.

The other options, such as dehydration, damaging the liver, or inducing paralysis, do not accurately describe the mechanism by which anticoagulant rodenticides operate. While other toxicants may cause such effects, anticoagulant rodenticides specifically target the blood’s ability to clot, making option B the correct understanding of their action.