Final answer:
The statement in question is false. Reaction time varies with physical condition, age, fatigue, and other factors, and is not constant as suggested.
Step-by-step explanation:
The statement 'Reaction time is always constant and is not affected by physical ability, age, or fatigue.' is false. Reaction time can be significantly influenced by a variety of factors including physical ability, age, health, level of fatigue, and even the degree of focus and concentration a person has at any given moment. The reaction time experiment with a ruler is a simple way to measure this variable attribute. For example, as one ages, reaction times may slow due to changes in nerve conduction and muscle response. Fatigue can also slow reaction times as it affects cognitive function and muscle coordination. Therefore, stating that reaction time is constant disregards the physiological and neurological complexities involved in the process of reacting to stimuli.