Overall brain slowdown is evident in which of the following ways?
a) faster reaction time
b) slower reaction time
c) faster thinking
d) faster talking

The answer is letter B. 

Motor neurons tend to function less as age sets-in in a particular individual. Reaction time is the ability to respond quickly to stimulus presented in a given situation. An example of this is the gun start that is commonly used in athletic competitions where a person reacts quickly to the signal and performs the activity. As we age, our sensory systems deteriorate and as a result some of the skills we have when we were younger are not as effective as it was when we turned into mature adults.