Marilyn was asked to solve a series of five math problems. the first four problems could only be solved by a particular sequence of operations. the fifth problem could also be solved following this sequence; however, a much simpler solution was possible. marilyn did not realize this simpler solution and solved the problem in the way she had solved the first four. her problem-solving strategy was hampered by:
a. functional fixedness
b. the overconfidence phenomenon
c. mental set
d. her lack of a prototype for the solution