Answer: Representatieness heuristic
Explanation: Representativeness heuristics occurs when someone tries to draw a conclusion or make a decision about something, using heuristic representativeness, which means that they make a conclusion based on stereotypes. In this particular case, the teacher used this mental shortcut based on her knowledge of who, according to his usual behavior, could throw a baseball on the classroom floor. This kind of decision-making and conclusion can often be wrong, though in this way decisions are made quickly, but still based on stereotypes, which may not always be a good direction in decision-making.