The core purpose of （ ） is to ascertain the allocation of application software segments to respective hardware platforms. This necessitates the identification of the key software components under development, followed by their assignment to the diverse hardware elements upon which the system will reside. All software systems can be categorized into four fundamental roles. The initial role pertains to （ ） . The majority of information systems necessitate the storage and retrieval of data, be it a miniscule file, akin to a word processor's memo, or an extensive database housing an organization's financial records. The subsequent function is the （ ） , encompassing the procedures necessary for data access, often executed through Structured Query Language database queries. The third function revolves around the （ ） , which encapsulates the logic articulated in DFDs, use cases, and functional specifications. Lastly, the presentation logic oversees the display of information to the user and the reception of user commands. The three fundamental hardware constituents of a system encompass （ ） .