When does a false negative occur?

Correct answer: The model predicts negative, but the actual condition is positive.

Direct answer: A is correct. In a classification problem, first identify the actual condition and then compare it with the model’s prediction. A positive case is one in which the condition is truly present; a negative case is one in which it is absent. A false negative happens when the condition is actually positive, but the model incorrectly predicts negative. It is called “false” because the negative prediction is wrong. Option B is a true positive: the condition is positive and the prediction is positive. Option C is a true negative: both the actual condition and prediction are negative. Option D is a false positive: the model predicts positive even though the actual condition is negative. A useful memory cue is “false negative = missed positive.” In a medical screening example, an affected person incorrectly reported as unaffected is a false negative.