Which succinct definition best describes 'flexibility' as a component of physical fitness?

• A. The ability of a joint to move through its full range of motion without pain or significant restriction.
• B. The percentage of body mass composed of contractile tissue such as muscle, typically measured with body composition analysis rather than joint testing.
• C. The speed at which a limb can be moved through a joint's range of motion under maximal power output, as measured by isokinetic dynamometry at extremely high angular velocities.
• D. The amount of force a muscle can exert in a single maximal contraction, typically assessed by 1RM testing at the joint being measured.

Answer: (A)