Margaret is solving the linear equation 3(x+4)=42 . As she was solving, she took the equation 3(x+4)=42 , performed an algebraic operation and ended up with 3x+12=42 . Which algebraic property justifies this operation?
 A) Multiplication Property of Equality
 B) Division Property of Equality
 C) Associative Property
 D) Distributive Property