Step 1: Recall significance.
National Fish Farmers Day is celebrated in India to honor fish farmers and recognize their contribution to aquaculture and fisheries.
Step 2: Historical reason.
The date 10 July marks the success of induced breeding of Indian major carps (Rohu, Catla, Mrigal) achieved by Dr. Hiralal Chaudhary and Dr. Alikunhi in 1957.
Step 3: Conclusion.
Hence, National Fish Farmers Day is observed on 10 July.
Final Answer: \[ \boxed{\text{National Fish Farmers Day is celebrated on 10 July.}} \]
Fill in the blank with the correct option.
The teacher believed that the student’s sudden lack of interest in class was an ..........., as he had always been enthusiastic and attentive.