**Core Concept**
Permethrin is a synthetic pyrethroid insecticide widely used for treating bed nets in areas where malaria is endemic. It acts by disrupting the insect nervous system, ultimately leading to the death of the mosquito.

**Why the Correct Answer is Right**
Permethrin binds to the sodium channels of the insect nervous system, causing sustained depolarization and repetitive firing of action potentials. This leads to muscle paralysis and ultimately death of the mosquito. The use of permethrin-treated bed nets has been shown to significantly reduce the incidence of malaria in endemic areas by preventing mosquito bites.

**Why Each Wrong Option is Incorrect**
**Option A:** DDT is an older insecticide that was widely used for malaria control, but it has been largely phased out due to concerns over resistance and environmental toxicity.

**Option B:** Pyrethrin is a natural insecticide derived from chrysanthemum flowers, but it is not as stable or effective as permethrin for use on bed nets.

**Option C:** Lindane is an organochlorine insecticide that is no longer recommended for use on bed nets due to concerns over toxicity and environmental persistence.

**Clinical Pearl / High-Yield Fact**
Permethrin-treated bed nets are a critical tool in malaria control, but their effectiveness can be reduced if they are not properly washed or re-treated every six months to maintain their insecticidal efficacy.

**Correct Answer: C. Permethrin**