Correct Answer : Option (C) : optical microscope
Explanation : Microstructures are examined by optical microscopy, by scanning electron microscopy and by transmission electron microscopy.
Ultrasonic imaging is used for detecting defects in a component.
The acoustic waves penetrate the material, enabling one to study the microstructure of material within the volume, to detect small defects, to study adhesive interfaces, and also to gain information about elasticity as well as absorption.
