The correct answer is: A. System Implementation
File conversion is the process of converting data from one format to another. It is often used when a new system is being implemented and the data from the old system needs to be converted to the new format. File conversion can also be used to update data or to make it compatible with different software applications.
System implementation is the phase of the systems development life cycle (SDLC) in which the new system is put into operation. This includes testing the system, training users, and making any necessary changes. File conversion is often a part of the system implementation phase, as it is necessary to convert the data from the old system to the new format.
The other options are incorrect because they do not involve file conversion. System analysis is the phase of the SDLC in which the current system is analyzed to identify its strengths and weaknesses. System development is the phase in which the new system is designed and built. System design is the phase in which the architecture of the new system is defined.