The correct answer is: A. Normal time
Normal time is the amount of time it takes to complete an activity at a normal pace without any overtime or additional resources. It is the time that is used to calculate the project’s duration and cost.
Slow time is the amount of time it takes to complete an activity at a slower pace than normal. This may be necessary if there are constraints on the availability of resources or if the activity is not critical to the project schedule.
Crash time is the shortest amount of time it takes to complete an activity. This can be achieved by using overtime, additional resources, or other means. However, crash time is usually more expensive than normal time.
Standard time is a combination of normal time and crash time. It is the amount of time it takes to complete an activity at a standard pace, which is somewhere between normal time and crash time. Standard time is often used to calculate the project’s contingency time.