Final answer:
The term for a hard covering or shell that provides protection and muscle attachment is exoskeleton. A fusiform shape refers to a shape that is tapered at both ends. Dolphins have a fusiform shape.
Step-by-step explanation:
The term for a hard covering or shell that provides protection and muscle attachment is exoskeleton. This structure is found in many invertebrates such as insects, crustaceans, and arachnids. It serves as a protective barrier and also provides support and attachment points for muscles.
A fusiform shape refers to a shape that is tapered at both ends, resembling a spindle or a torpedo. In the given options, the organism that has a fusiform shape is the dolphin. Dolphins have streamlined bodies that allow them to swim efficiently through the water.