Answer: OPTION C.
Explanation:
 The standard form of a Quadratic equation is:
 

 Where "a", "b", and "c" are numerical coefficients (
 )
)
 The term 
 is the Quadratic term,.
 is the Quadratic term,.
 The term 
 is the Linear term.
 is the Linear term.
 The term 
 is the Constant term.
 is the Constant term.
 A Quadratic equation whose Linear term is not present, is called a "Pure quadratic equation", and can have the following form:
 

 Based on this, we can determine that the equation shown in Option C is a Pure quadratic equation, because it has a Quadratic term and a Constant term:
 

 It can be written as:
 
