DFD graphically representing the functions, or processes, which capture, manipulate, store, and distribute data between a system and its environment and between components of a system. There are four basic symbols that are used to represent a data-flow diagram. The visual representation makes it a good communication tool between User and System designer. Structure of DFD allows starting from a broad overview and expand it to a hierarchy of detailed diagrams.
The number of distinct symbols that can be used in DFDs is Four.
Hence Correct Answer is d) Four
