Final answer:
The sea bass uses a swim bladder for neutral buoyancy. The swim bladder is an adjustable organ that helps fish control their buoyancy without expending energy, although some fish like sharks have developed other mechanisms for this purpose.
Step-by-step explanation:
The animal that uses a swim bladder to achieve neutral buoyancy from the options provided is sea bass. The swim bladder, a gas-filled sac, is present in many bony fish and enables them to control their buoyancy for maintaining their position at different water depths without wasting energy. Sharks, for instance, do not have swim bladders; instead, they rely on their liver, which contains oil, and their cartilaginous skeleton, which is less dense than bone, to maintain buoyancy.
A swim bladder is significant because it allows fish to have an adjustable buoyancy. This organ can be inflated or deflated to change the fish's density relative to the water, which helps them to either rise or sink in the water column. Some fish, however, like sharks, have evolved alternative mechanisms such as the use of oils and their lightweight cartilaginous skeletons to remain neutrally buoyant without the need for a swim bladder. This evolution might be due to different ecological niches these fish occupy, which do not require the fine-tuned buoyancy control that a swim bladder provides.