Public opinion can never be any sounder than when it is based on ?

even though you have attached neither the chart nor the generalizations, i have located them online. the right answer is d, since they are asking you about a generalization. you can only infer from the chart that between 2008 and 2009 the number of employed workers decreased significantly (from over 115 millions to 107 millions approximately), which signals some type of economic crisis.  

answer; have joints that fail from excess by early the accumulated effects of unnoticed infections,all of these things are possible for a person born without the ability to feel pain;