This forms the basis of all extruded parts. A.
Constraints
B.
Dimensions
C.
Model
D.
Sketch

The correct answer is b, social stratification is needed for a society to exist. marxist theory regarding social stratification is that due to the differing economic capacities among people in society, a natural separation occurs between those that own the means of production and those that sell their labour in the production chain. 

Iwould tell u but its against rules

Number 3 is the logical, go-to answer for the classical school of thought as they strongly believe that an individual commits a crime of their own free will and fully understands the  consequences, making them liable to whatever punishment is dealt to them. 

Maybe because he failed the classes or is very accelerated.