Final answer:
A static ancestor is the subprogram that contains the definition of another subprogram, determined at compile-time, while a dynamic ancestor is the subprogram instance that calls another subprogram at runtime, which can change during execution.
Step-by-step explanation:
The concepts of static ancestor and dynamic ancestor pertain to the calling context of a subprogram in programming languages that support nested subprograms, such as Ada, and to certain object-oriented programming languages.
A static ancestor of a subprogram is the subprogram that contains the definition of another subprogram. This relationship is determined at compile-time, and it does not change during the execution of the program. For example, if a function A contains the definition of a nested function B, then A is the static ancestor of B.
A dynamic ancestor, on the other hand, refers to the actual subprogram instance that made the call to another subprogram at runtime. This can change each time the subprogram is executed. In simple terms, if subprogram A calls subprogram B, then at that moment of execution, A is the dynamic ancestor of B.