Option C I'd say.
Hope you find it helpful!
Observing and measuring (A)
<span>Fungi decomposes organic matter in soil and secrete extracellular enzymes that digest material and absorb simple organic molecules from the environment. </span>
Answer:
A is the eyepiece (or ocular lens), B is the objective lenses, C is the iris diaphragm, D part is refers to light condenser, E is the location of fine adjustment knob and F is the location of coarse adjustment knob.
Explanation:
A is the eyepiece (or ocular lens), B is the objective lenses, C is the iris diaphragm, D part is refers to light condenser, E is the location of fine adjustment knob and F is the location of coarse adjustment knob. All these parts are the important parts of microscope which has a specific function in the microscope. Without one of these parts, we can not see the microbes in the microscope.