Final answer:
A combinatorial logic circuit is characterized by the absence of memory retention of its inputs, meaning it does not store information or have feedback loops. Its output is based solely on the current combination of inputs.
Step-by-step explanation:
The characteristic associated with a combinatorial logic circuit is that it does not retain memory of its inputs or past behavior. Unlike sequential circuits, combinatorial logic circuits do not have the capability to store data or maintain a history of the inputs that have been applied to them. The output of a combinatorial logic circuit is determined solely by the current combination of inputs without regard to previous inputs. Therefore, the correct answer to the student's question is A) Memory retention of inputs.
Regarding the options given:
- Sequential processing and Feedback loops are characteristics of sequential logic circuits.
- Memory characteristics are associated with circuits that can retain state, such as flip-flops and latches, which are also found in sequential circuits.