Hint: An electron microscope is a microscope that takes a beam of accelerated electrons and illumination as a source. The wavelength of an electron can be taken of more than 100,000 times shorter than that of visible light photons.
Complete step-by-step answer:
Electron microscopy has several different forms of applications in practice. The ability to observe the microscopic structure of a specimen at a higher resolution than what is possible with optical microscopy gives it a distinct role in scientific research and industry applications. Electronic microscopes are generally used in research laboratories, universities, and nanotechnology centres.
Now let’s see the type of lenses present in electron microscopes;
> Electric: These are also known as Electrostatic lenses. These lenses are used in transportation of charge particles. It guides the transmission of electrons from a sample to the electron’s analyser. So, it helps to transmit light.
> Photoelectric: These are used in photographic cameras to obtain a good and high-quality image. It is also used to absorb photoelectric effect which is the ejection of electrons when light strikes the surface of metal.
> Electromagnetic: It is a lens which is used to converge the electron beams. It is generally made up of solenoid wire that remains connected with a magnetic pole which in turn creates a strong magnetic field. It can be seen used in modern day instruments such as electron microscopes.
> Quartz: It is used to make lenses which are used in making the instruments of ultraviolet radiations. It is used to make the substrates of precision mirrors and also the watches.
Hence, the correct answer is option (C). Electromagnetic.
Note: One of the most beneficial uses of an electron microscope is its superbly high magnification power which is simply not achieved by any other type of microscope, for example conventional light microscopes.