Which of the following is a symptom of Hematologic Syndrome during the prodromal phase?

During the prodromal phase of Hematologic Syndrome, symptoms manifest as the body begins to react to the effects of radiation exposure on the hematologic system. This phase typically occurs shortly after exposure to a high dose of radiation and can include various nonspecific symptoms.

Nausea is a well-known and commonly experienced symptom during this phase, as the gastrointestinal system is often affected by radiation. It arises due to the damage to the cells in the gastrointestinal tract, as well as a general response to the body's distress.

Fever is generally more associated with the following stages of radiation syndrome where immune system compromise can lead to infections, while confusion and seizures are indicative of neurological involvement, which is not directly part of the hematologic symptoms.

Therefore, nausea specifically aligns with the expected symptoms experienced in the prodromal phase of Hematologic Syndrome.