♥ $$\times$$ ☺ $$=$$ ♦  Since ☺ is an even number,~♦ must also be an even number.  ♦ $$-\textasciitilde3$$ is the only option to given an odd answer because even $$-$$ odd $$=$$ odd. 
♥ $$\times$$ ☺ $$=$$ ♦  ☺ is an even number.  which of the following gives an odd answer? 

a) ♦ $$-\textasciitilde3$$ 
b) ☺ $$+$$ ♦ 
c) ☺ $$\times$$ ☺ 
d) ♦ $$\times$$~♦ 