Question $1$

To open a file c: $\backslash$scores$.$txt for reading, use

infile $=$ open$("$c:$\backslash$scores$.$txt$","$r$")$

infile $=$ open$("$c: $\backslash$scores$.$txt$","$r$")$

infile $=$ open$($file $="$c:$\backslash$scores$.$txt$","$r$")$

D$.$ infile $=$ open$($file $="$c:$\backslash$scores$.$txt$","$r$")$