Span Prediction Loss Formula

A question-answering model is being trained to identify a specific answer span within a passage. The model's training objective is to minimize a loss calculated from two separate predictions for each token: the probability of it being the start of the answer and the probability of it being the end. The total loss is calculated by summing the negative log-likelihoods from both prediction networks. In which of the following scenarios would the model incur the highest training loss for a single training example?

Analyzing Span Prediction Model Loss

Rationale for Combined Span Prediction Loss