Final answer:
Informed consent is required before performing ultrasonography, mammography, fine-needle biopsy (FNB), or an MRI.
Step-by-step explanation:
Before performing ultrasonography, mammography, fine-needle biopsy (FNB), or an MRI, informed consent is required. Informed consent is the process in which a patient is provided with information about the procedure, its risks, benefits, and alternatives, and gives their voluntary consent to undergo the examination.