The correct option is:
B. scanning tunneling microscope
Explanation:
A scanning tunneling microscope is an instrument for imaging surfaces at the atomic level. Its expansion in 1981 introduced its inventors, Gerd Binnig and Heinrich Rohrer, the Nobel Prize in Physics in 1986. The scanning tunneling microscope (STM) is a type of electron microscope that shows three-dimensional images of a sample. In the STM, the structure of a surface is considered using a graver that scans the surface at a set distance from it. A remarkably fine conducting probe is held near to the sample.