In an assignment statement a=b; which of the following statement is true ?

[A] The variable a and the variable b are same.

[B] The value of b is assigned to variable a but if b changes later, it will not effect the value of variable a.

[C] The value of b is assigned to variable a but if b changes later, it will effect the value of variable a

[D] The value of variable a is assigned to variable b, and the value of variable b is asssigned to variable a.