Which of the following tools would a project manager use to determine the root cause of an issue?

A Pareto Chart is used to identify the most significant factors in a dataset, typically showing which 20% of causes are responsible for 80% of problems, but it does not delve into the root causes themselves.

An Ishikawa Diagram, also known as a fishbone or cause-and-effect diagram, is a quality management tool used to brainstorm and visually organize potential causes of a specific problem. It helps in systematically exploring all possible factors contributing to an issue to identify its root cause.

A Histogram is a graphical representation of the distribution of numerical data, showing the frequency of different values, and is not used for root cause analysis.

Monte Carlo Analysis is a simulation technique used to model the probability of different outcomes in a process that cannot easily be predicted due to random variables, not for identifying the root cause of an existing issue.