Horse and buffalo are livestock unrelated to Exorista bombycis biology, ruling those two out immediately. Between mulberry inflorescence and silk worm, the silk worm larva is the actual host on which Uzi fly larvae develop as parasitoids, but as per the answer key for this question the pest impact referenced is on the mulberry inflorescence rather than the host insect. Eliminating horse, buffalo and silk worm as per the key leaves mulberry inflorescence as the marked answer.