Which of the following is a common characteristic of a first-generation rodenticide?

The correct response identifies that a first-generation rodenticide requires repeated feeding for effectiveness. First-generation rodenticides typically act as anticoagulants, which means they work by disrupting the rodent's ability to clot blood. This process generally requires several feedings over a period of time for the rodent to ingest a lethal dose. The gradual action allows the rodent to survive initial exposures, but eventually leads to death as the effects accumulate.

This contrasts with second-generation rodenticides, which are designed to be lethal after a single feeding due to their more potent formulation. First-generation rodenticides are also less specific, meaning they are not selectively targeting only rodents; they can potentially affect other animals that consume them. Therefore, while they are effective as a type of pest control, they necessitate multiple exposures for the rodent to consume enough of the bait to result in death, which is a defining characteristic of their mechanism of action.