Question $21(2\mathrm{.}5$ points$)$

Which of the following expressions might use short$-$circuit evaluation?

$$ a$)$ if $x==3$ and $y>0$ :

b$)$ if $x==3$ or $y>0$ :

c$)$ if $n>0$ and total $/$ float $(n)>90\mathrm{.}0$ :

d$)$ all of the above

e$)$ none of the above