This is a programme target recall item. India committed to eliminate lymphatic filariasis as a public health problem by the year 2015, a target driven by repeated rounds of mass drug administration where the at risk community swallows diethylcarbamazine plus albendazole once a year. The aim of these rounds is to drive microfilaria rates below the threshold needed to sustain transmission by the mosquito vector. Malaria sits under a control and reduction strategy rather than a fixed 2015 elimination year here. Tuberculosis follows the RNTCP control pathway with much later elimination ambitions. Kala azar also carried a 2015 ambition but mainly in the endemic eastern states, while filariasis was the nationwide 2015 elimination disease that fits the key. Hence filariasis is the intended answer. $$\boxed{\text{Filariasis}}$$