The correct answer is option 2, the continental shelf.

The Bombay High oil fields are located on the continental shelf, which is a part of the submerged edge of a continent. The continental shelf is relatively shallow and gradually sloping compared to the other relief features mentioned in the options.

Option 1, the continental slope, is a steeply inclined region that connects the shelf to the deeper ocean floor. It is not the correct answer in this case.

Option 3, the continental rise, is a gently sloping region found at the base of the continental slope. It is formed by accumulations of sediment and is not the correct answer for the location of the Bombay High oil fields.

Option 4, the ocean basin floor, refers to the deep ocean floor beyond the continental shelf. It is not the correct answer because the Bombay High oil fields are not located in this region but rather on the continental shelf itself.

In summary, the correct answer is option 2, the continental shelf, as the Bombay High oil fields are situated on this submerged part of the continent.