. . . . . . . . is the intensive method of vegetable cultivation.

Truck gardening is the intensive method of vegetable cultivation. It involves the cultivation of a variety of vegetables on a relatively small piece of land and is often practiced for commercial purposes. Truck gardens are typically located close to urban areas to ensure the supply of fresh vegetables to local markets. This method allows for the efficient and intensive cultivation of vegetables to meet the demands of local consumers. It's an important aspect of horticulture, especially in providing fresh produce to urban populations.

The other options are:
Option A: Market gardening is another term for the same concept as truck gardening, involving intensive vegetable cultivation for local markets. Option C: Kitchen gardening is a smaller-scale cultivation method in which individuals or families grow vegetables for personal consumption near their homes. Option D: Floating gardening refers to a method of growing crops on water bodies, often used in regions with abundant water resources.

So, the correct answer is Option B: Truck gardening, which specifically relates to intensive vegetable cultivation for commercial purposes.