Due in large part to the complexity of its structure--over two hundred bones ______ together by lint

Due in large part to the complexity of its structure--over two hundred bones ______ together by lints--the human skeleton is a marvel of architectural construction. A. binging B. bound C. bounded D. bind

The correct answer is B. bound. This sentence requires a past participle to form a reduced adjective clause describing the bones. "Bound" (the past participle of "bind") properly conveys that the bones are connected by ligaments, functioning adjectivally to modify "bones."

A. binging is incorrect as it refers to excessive eating/drinking and is unrelated to physical connection.

C. bounded means "limited" or "jumped," which doesn’t fit the context of structural connection.

D. bind is the base verb form and cannot function as a modifier in this sentence structure.

Understanding participle usage helps clarify why "bound" works here—it acts as an adjective describing the state of the bones, creating a concise description of the skeleton’s complex architecture. How might this sentence change if we used a full relative clause instead of the participle?