They are all used to measure volume
When the light bounces off an object and travels to your eyes those light rays travel parallel to each other. When they pass through a magnifying glass, the Convex lens finds the parallel rays so that they converge and create a virtual image on your eyes retinas. The virtual image on your retinas appear larger than the real object due to principles of Geometry. Despite the magnifying glass, your eyes trace the light rays back in parallel lines to the virtual image. Since the virtual image is farther from your eyes than the object is, the object appears bigger.
The answer possibly could be a drought but I’m not 100%
B. Mitochondria
The process of cellular respiration is essentially when oxygen and carbon transfuse themselves together to create carb on dioxide, which in turns creates energy.
The entire process is formed in the powerhouse of the cell, or in other words, the mitochondria.
A part of this question that may have been confusing is the answer, "lungs". Since respiration is correlated to the lungs, you may have been confused. However, this is a process that occurs within your cells, so on a small scale than your entire body.
