The correct answer is option 3, Ostrich.

Option 1, Eagle: While eagles are impressive birds, they are not the largest living bird. Eagles vary in size, with the largest species, the Steller`s sea eagle, weighing around 15 pounds.

Option 2, Peacock: Peacocks are known for their vibrant feathers, but they are not the largest living bird. Male peacocks have long tails that can reach up to 5 feet in length, but their body size is much smaller compared to other birds.

Option 4, Kiwi: Kiwis are flightless birds native to New Zealand. While they are interesting birds, they are not the largest living bird. Kiwis are small and measure around 12-18 inches in height.

Overall, the Ostrich is the largest living bird, weighing between 220-350 pounds and standing around 9 feet tall. They are flightless and have long necks and legs, making them the largest of all bird species.