The fact that you may not know who your congressional representative is represents:
c. rational ignorance on your part.
Rational ignorance refers to the idea that individuals may choose not to acquire certain information because the cost of doing so exceeds the expected benefit.
In the context of knowing your congressional representative, individuals might choose not to invest time and effort in obtaining this information because the impact of their knowledge on the outcome of an election or policy decisions is generally very small.
As a result, people may rationally decide to remain ignorant about certain details of politics or government.