In 2016, the top-selling pharmaceutical drug in the world was AbbVie's Humira, which is used for the treatment of several common, chronic conditions. The majority of its profits are derived from treatment of the most common diseases, so why does AbbVie develop drugs for rare diseases instead of investing all of its resources toward drugs for common diseases? O AbbVie uses marginal analysis to earmark their funds. If the additions to revenues from a new cure for rare diseases exceeds the cost to generate the treatment, Abbvie would be wise to undergo the research and studies. O It is more costly to develop a cure for common diseases than it is to find a cure for rare diseases O There is too much competition in big pharmaceuticals so spending money on research for cures to common cures generates less of a gain than generating cures for rare diseases O Getting FDA approval is easier to obtain for cures for rare diseases than it is for cures for more common diseases Onone of the above.