Final answer:
The most likely condition among the given options is migraine headache without aura.
Step-by-step explanation:
The most likely condition among the given options is migraine headache without aura. Migraines are characterized by severe head pain that can be accompanied by nausea and other symptoms. Migraines often occur without aura, which refers to visual disturbances like flashes of light or blind spots that can precede the headache. While cluster headaches, migraines with aura, and giant cell arteritis are all possible conditions, migraine headache without aura is the most likely option based on the information provided.