In the context of fairness, the attributes that are considered sensitive are those that, if used in decision-making processes, could lead to discrimination or unfair treatment. In the given event log, the sensitive attributes are:

1. case:citizen: This attribute indicates whether the patient is a citizen or not. It could potentially lead to unfair treatment based on nationality or immigration status.
2. case:german speaking: This attribute indicates whether the patient speaks German or not. It could potentially lead to discrimination based on language skills or national origin.

These attributes are considered sensitive because decisions based on them could potentially create biases, leading to unequal treatment or opportunities for different groups of people. It's important to ensure that any decisions made using process mining techniques are fair and do not discriminate against certain groups.