Answer:
The correct answer would be - Dominant hand of the individual.
Explanation:
The response time is always faster in the dominant part of the body as the brain has developed strong signaling over the course of the time. This is because one uses his or her dominant hand for most of the actions so the nerves are become skilled to do their job in comparison of the other hand.
The dominant hand will catch the ruler faster as it is skilled and the brain sends signals in fractions of the second in this case the primary response takes place in this case.
Thus, the correct answer is - the dominant hand of the individual.
