Distinguish between the near field and far field of an ultrasonic beam.

• A. The near field is the region close to the transducer where the beam is still developing.
• B. The near field is the region far from the transducer where the beam is stable and diverging.
• C. The far field is the region close to the transducer where the beam diverges.
• D. The far field is the region where the beam is not yet formed.

Answer: (A)