An electron microscope would be used if

For viewing ultra- structure

Explanation:

When any object, substance or biological specimen is so small that it cannot be viewed through normal optical telescopes then it become essential to use electron microscope. Thus electron microscope are used for inspecting wide range of  ultra-structure

In an electron microscope , a beam of electron is thrown on the object which makes it advantageous over and above normal optical microscope which have certain limitations due to the limitations associated with light .

answer; the correct answer is conflict- related aggression; +

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).