Why is commensalism called commensalism

Can someone me with this and tell me what’s fracking and what does it have to do with carbon, carbon dioxide, or fossil fuels?

Which of these is not an example of molecular homology? 1. use of dna and rna as genetic material 2.use of glycolysis as the first step in cellular respiration in both plants and animals 3. the lack of an igf-1 gene in prokaryotes 4. the use of aldolase b to break down fructose in bacteria, plants and animals

Has magnification ability of hundreds of thousands of times