Is F one$-$to$-$one? Why or why not?

F is one$-$to$-$one because each element of Y is the image of some element of X$.$

F is one$-$to$-$one because no two elements of X are sent by F to the same element of Y$.$

F is one$-$to$-$one because g is in Y but g $!=$ F$($x$)$ for any element x in X$.$

F is not one$-$to$-$one because each element of Y is the image of some element of X$.$

F is not one$-$to$-$one because F$($c$)=$ e $=$ F$($d$)$ and c $!=$ d$.$