Final answer:
A burst activity is a task leading to multiple subsequent tasks, and a merge activity is one that follows two or more tasks. Dummy activities are used to show correct relationships without representing actual work, and critical activities are ones any delay in which will delay the whole project.
The correct option is d.
Step-by-step explanation:
To answer your question, first, we need to define what a project network is. A project network is a visual diagram that represents the sequence of activities in a project, showing how each activity is connected to others.
Burst Activity
A burst activity is a single project task that is followed by multiple subsequent tasks. This is an activity from which two or more activities emerge. It indicates the point where the project diverges into two or more parallel tasks.
Merge Activity
A merge activity is an activity that follows two or more tasks. It signifies the point where parallel tasks converge into a single subsequent task.
Dummy Activity
A dummy activity is a fictitious task, represented by a dashed arrow, that is used in project networks to establish correct precedence relationships between tasks when a direct connection does not exist or to avoid misrepresentation of the logical relationships.
Critical Activity
A critical activity is a task that is on the critical path, meaning that any delay in this activity will result in a delay of the project's end date. The critical path itself is the sequence of activities which add up to the longest overall duration, determining the shortest time to complete the project.
The correct option is d.