Which is a contact fungicide?

Answer: Option C

Captan is a contact fungicide.
Captan is a dicarboximide that is 3a,4,7,7a-tetrahydrophthalimide in which the hydrogen attached to the nitrogen is replaced by a trichloromethyl group.
Captan works by coming into contact with a fungus and interrupting a key process in its life cycle. It can be toxic to many different fungal diseases. Captan is non-systemic, which means it is not expected to move through plants.