What type of farming is likely associated with Indiana's agricultural output of ducks?

Poultry farming is the correct answer because it specifically involves the raising of birds for meat, eggs, and other products, which includes ducks. Indiana has a diverse agricultural sector, and poultry farming plays a significant role in the state's economy. Ducks are categorized under poultry, making this type of farming the most relevant for the production of ducks.

In contrast, dairy farming focuses primarily on the production of milk and dairy products, which does not encompass ducks. Crop farming, on the other hand, is dedicated to the cultivation of plants like grains, vegetables, and fruits, meaning it would also not involve the raising of ducks. Livestock ranching is mainly concerned with larger animals such as cattle, sheep, and goats, further distancing it from the focus on poultry, including ducks. Thus, the association of ducks with poultry farming stands as the most appropriate choice.