Commercial agriculture involves farming practices that are designed to produce crops and livestock for sale on the market.

Option 1, dairy farming, is a type of commercial agriculture, as dairy products like milk, cheese, and butter are commonly produced for sale.

Option 2, grain farming, is also a commercial agriculture type since grains like wheat, corn, and rice are typically cultivated for market sale, sometimes on a large scale.

Option 3, livestock ranching, is a form of commercial agriculture too. Large numbers of animals like cattle or sheep are usually raised for meat, wool, and other products to be sold in markets.

Option 4, intensive subsistence agriculture, is not a type of commercial agriculture. It involves cultivating small amounts of land with a high level of input per unit area, usually for dire consumption, not selling on the market. Thus, the correct response is option 4.