Why wouldn't you make this simpler by:
string key_pressed = Console.ReadLine().ToUpper();
switch (key_pressed)
{
case "A":
case "B":
case "C":
case "D":
if(levels[current_level][x][5] == key_pressed)
{
}
else
{
}
break;
case "1":
break;
case "2":
default:
break;
}
you won't have to do so many checks