What is known as linguistics problems

Linguistic problems and complexities can be classed as lexical, syntactic or semantic depending on their context. Lexical problems involve the interpretation of particular words or phrases rather than entire classes. These problems exist independent of context although they are only evident in it.

Explanation:

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; the responsibility of all person, including civilians and contractors;