The diaphragm is to the thoracic cavity and to the pelvic cavity.
inferior; superior
superior; anterior
posterior; inferior
superior; inferior

The correct answer for the fill in the blank is - inferior; superior.

Diphragm is a thin muscular and membranous sheet like structure that separates thoracic cavity ( chest cavity) from abdominal cavity. It is present below lungs and heart and therefore lies inferior to the thoracic cavity ( chest). It is a primary muscle involved in respiration.

As it separates chest from abdomen, therefore it lies superior or above the pelvic cavity ( present in the pelvic region that lies between abdomen and thighs).

Thus, diaphragm is inferior to the thoracic cavity and superior to the pelvic cavity.

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