Consider of the following piece of pseudocode. Which of the following is a valid invariant of the

loop? Circle ALL that apply.

A$.x>0$

B$.xb$

C$.x+b**y=a$

D$.x+b**y=b$

E$.y+a**x=a$

F$.y+a**x=b$

G$.yb$

$//$ Precondition: $a0$ and $b>0$

Mystery$($a$,$ b$)\{$

$x=a$;

$y=0_{{?}_{?}}$

while $(xb$

$x_{{?}_{?}}=x-b$;

$y=y+1$;

$\}$

return $x_{\text{;}}{?}_{?}$

$\}$