The answer is D. Data flow analysis is used to study the intrinsic complexity of the code. Without the use of data flow analysis studies, it would be extremely difficult (if not even impossible) to study the intrinsic complexity of the code.
This analysis helps the data easier for people to comprehend and use it to test different properties of the code which then allows people to manage and evaluate it easier. In order to collect information about different values after they are calculated periodically, you must use the technique called data flow analysis. Once this step is complete, the analysis will present the data in a flow graph.
The data flow analysis is a special technique that is employed to gather information from a particular set of values which are calculated at certain points in the system. Then the program makes a control flow graph which determines the different parts of a program to which certain values should be assigned to a variable and where they will propagate.
The data flow analysis basically studies the intrinsic complexity of the code and makes it easier for others to understand. Using it you can analyze the different aspects of the code and understand how to evaluate and manage it effectively.