Human diseases (parasitology): Identify the causative agent of filariasis (filaria) in humans. Focus on the pathogen class and typical transmission route. Choose the correct cause.

Given data

• Disease: Filaria (lymphatic filariasis).
• Ask: Causative agent.

Concept/Approach
Lymphatic filariasis is caused by filarial nematodes such as Wuchereria bancrofti and Brugia spp., typically transmitted by Culex, Anopheles, or Aedes mosquitoes.

Reasoning
• Worm infection (helminth) → not bacterial, protozoal, or fungal. • Vector: mosquitoes inject larvae that mature in lymphatics.

Final Answer
Filarial nematode worms (e.g., Wuchereria bancrofti) transmitted by mosquitoes