Final answer:
Tanya is experiencing fixation, which is the inability to see the problem from a new perspective and continuing to use a problem-solving strategy that is not working. So the correct option is A.
Step-by-step explanation:
Tanya is experiencing an obstacle to problem-solving known as fixation. Fixation occurs when a problem solver cannot see a problem from a fresh perspective, and becomes stuck on one way of looking at the issue. This can happen when an individual focuses solely on a single aspect of the problem or employs a problem-solving strategy that has worked in the past, despite it not being effective for the current problem.
Fixation is different from other biases like counterproductive heuristic, which refers to a mental shortcut that leads to inefficient or incorrect outcomes; confirmation bias, which is the tendency to seek out information that supports preexisting beliefs; or overconfidence, which is the belief that one's abilities or predictions are more accurate than they are.