Concept:The total area under a probability density curve represents the total probability, which is always 1.
Explanation:The normal curve is a probability density function of a continuous random variable.
The total area under any continuous probability density function is always 1.
This is because the sum of probabilities of all possible outcomes must equal 1.
Options B and C represent 0.5, which is incorrect.
Option D is incorrect because the area is fixed at 1, not any value between 0 and 1.
Answer:The total area of the normal curve is one.