Identifying the root cause analysis. Identifying the root cause analysis is a quality assurance tool that can help to find and eliminate the underlying causes of quality problems or defects. Root cause analysis is a systematic process of asking why a problem occurred and tracing it back to its source. Root cause analysis can help to prevent recurrence of the same or similar problems, improve quality performance, and reduce costs and risks12

Comprehensive and Detailed Step-by-Step
A network diagram visually represents the sequence of activities and their dependencies in a project. It helps in identifying the critical path, which is the longest sequence of dependent tasks that determine the project's overall duration.
Reference:
CompTIA Project+ PK0-005 Official Study Guide, Chapter 5: Project Scheduling and Planning

The dependency between software installation and desktop installation is a mandatory dependency. A
mandatory dependency is a type of dependency that is inherent in the nature or logic of the work and cannot be
avoided or changed. It is also known as a hard dependency or a hard logic dependency. A mandatory
dependency means that one task must be completed before another task can start or finish. For example,
software installation can only start after desktop installation is finished5
The dependency between desktop installation and software installation represents a mandatory dependency. A
mandatory dependency is a type of task dependency that is inherent in the nature of the work being performed.
In this case, software installation cannot begin until desktops are installed and powered on, and therefore, the
dependency is mandatory. References: CompTIA Project+ Study Guide, Chapter 3: Project Integration
Management, Objective 3.1: Identify the project management processes and the interactions between them.

A burndown chart tracks how much work remains over time in an iteration (or release). The most direct inputs are the remaining work and the work completed (often expressed as tasks, story points, or hours). Therefore, to obtain burndown data efficiently, the PM should analyze remaining and completed tasks. This aligns with CompTIA Project+ Agile metrics concepts, where burn charts are used to visualize progress and forecast completion based on work remaining versus time.
The other options are not primary burndown inputs. "Number of people available" affects capacity and can influence how fast work burns down, but it is not what the chart directly measures. "Cost variance" is an earned value / financial control concept (more predictive/traditional) and not what burndown charts are built from. "Number of issues registered" is useful for quality and risk/issue tracking but does not represent the work remaining in the sprint backlog unless issues are explicitly counted as backlog items-and even then, the chart is still fundamentally about remaining work, not raw issue counts.
So, for efficient burndown extraction, the PM should use the team's work tracking (sprint backlog/task board) to calculate remaining vs. completed tasks/work, which is exactly what the burndown visualizes.

An Ishikawa diagram, also known as a fishbone diagram, is a tool used to identify and analyze the root causes of a particular problem. CompTIA Project+ references this tool as essential for quality management and problem-solving.