What type of injury involves the muscles or tendons that connect muscles to bones?

The correct choice is muscle strains, as this type of injury specifically involves the muscles and the tendons that connect those muscles to bones. A muscle strain occurs when the muscle fibers are stretched beyond their limits, leading to tears within the muscle or its tendons. This often results in pain, swelling, and limited mobility in the affected area.

Muscle strains typically happen during physical activity when muscles are either overloaded or subjected to sudden or excessive force. Understanding this definition helps clarify why muscle strains are categorized distinctly from other injuries like sprains, which affect ligaments connecting bones to other bones, and tendinitis, a condition involving inflammation of a tendon. Rotator cuff tears involve damage to specific muscles and tendons in the shoulder, but they represent a more complex injury than a basic muscle strain. Hence, muscle strains are the most accurate answer to describe injuries involving the muscles and their connective tendons to bones.