Final answer:
Chlorine is the most common organic contaminant removed by carbon filtration from municipal water sources, though activated charcoal can also filter out various other organic compounds.
Step-by-step explanation:
The most common organic contaminant removed by carbon filtration when using a municipal water source is chlorine. Chlorine is a widely used chemical in water treatment processes to disinfect and make water safe for human use, due to its effectiveness at killing bacteria and other pathogens. However, it can leave an undesirable taste and smell in the water. Activated charcoal filters are particularly adept at removing not only chlorine but also various organic compounds, including some byproducts formed by chlorine's reaction with organic matter in the water such as trihalomethanes. Alongside chlorine, activated charcoal efficiently absorbs a range of organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs). It's also worth noting that while charcoal effectively removes many organic contaminants, it does not typically reduce inorganic pollutants like arsenic and fluoride to the same degree.