Final answer:
The system investigation phase is mainly about gathering relevant data and determining the new system's requirements. Option C is correct.
Step-by-step explanation:
The purpose of the system investigation phase is to gather data on the existing system and determine the requirements for the new system.
This phase involves steps such as defining the problem, which is a process where the needs of potential customers and constraints such as government regulations, technological limitations, and resources like personnel, time, and money are investigated. This leads to a clear understanding of the scope of the project and is often expressed in a problem statement.
Additionally, during system investigation, there is an emphasis on gathering information from various stakeholders, performing a root cause analysis to pinpoint the true problem, and defining what is known and unknown about the system of interest, which helps in forming a complete picture of what the new system should achieve. It involves problem definition, stakeholder information gathering, root cause analysis, and identifying system constraints and unknowns.