Which type of pesticide is effective against slugs and snails?

The correct choice is molluscicides, which are specifically designed to target and control mollusks like slugs and snails. Molluscicides work by disrupting the biological functions of these pests, leading to their elimination. This type of pesticide contains active ingredients that are effective in managing populations of slugs and snails, making them a valuable tool in agricultural and gardening practices.

In comparison, insecticides are formulated to manage insect populations and are not effective against slugs and snails, which are not classified as insects. Nematicides are specifically intended to control nematodes, which are microscopic worms that can damage plant roots, and therefore would not be useful against slugs and snails. Fungicides are used to combat fungal diseases and have no relevance in controlling mollusks. Each of these other types of pesticides serves a distinct purpose, which does not include targeting slugs and snails, thereby reinforcing the significance of using molluscicides for these particular pests.