The generic name of the causal organism of Elephantiasis is Wuchereria bancrofti.

Let`s dissect each option to have a better understanding.

Option 1: Filaria - Filaria is a general term used to refer to a group of thread-like parasitic worms, including Wuchereria bancrofti. While Wuchereria bancrofti is a type of filaria, it is not the generic name itself.

Option 2: Microfilaria - Microfilaria refers to the larval stage of certain parasitic worms, including Wuchereria bancrofti. Again, microfilaria is a specific stage of the life cycle of the organism, not the generic name.

Option 3: Wuchereria bancrofti - This is the correct answer. Wuchereria bancrofti is the scientific or generic name of the causal organism of Elephantiasis. It is a parasitic worm that is transmitted to humans through mosquito bites.

Option 4: Culex pipiens - Culex pipiens is a mosquito species, not the causal organism of Elephantiasis. This mosquito species is known to transmit certain diseases, but it is not directly responsible for Elephantiasis.

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