Which will be output for the following Ruby Programming?

score $=89$

result $=$ case

when score $>=90$

$"$A$"$

when score $>=80$

$"$B$"$

when score $>=70$

$"$C$"$

else

$"$F$"$

end

puts "Your grade is #$\{$result$\}"$

A$.$ Your grade is $B$

B$.$ Your grade is $F$

C$.$ Your grade is $A$

D$.$ No output