Final answer:
The cribriform plate of the ethmoid bone serves as the passage for olfactory nerves, allowing smell sensations to be transmitted to the brain.
Step-by-step explanation:
The function of the cribriform plate of the ethmoid bone is to provide a passage for the olfactory nerves. The cribriform plate contains numerous small openings called olfactory foramina, through which small nerve branches from the olfactory areas of the nasal cavity pass to enter the brain. Therefore, option C) Passage for olfactory nerves is the correct answer to the student's question.
Located at the midline in the floor of the anterior cranial fossa, the cribriform plate forms part of the roof of the underlying nasal cavity and also contributes to the floor of the anterior cranial fossa. In contrast to the cribriform plate's role, the crista galli serves as an anterior attachment point for the dura mater, which is one of the covering layers of the brain. However, the cribriform plate's primary function remains focused on olfactory sensory transmission, allowing smell sensations to communicate with the brain.