1999 Lincoln Continental car makes a whining sound when i t

i been told a lot of deferrents things could be wrong with my car it makes a whining sound when i turn the wheel only to the right been told ilder wheel, struts, lower ball joints the boots on the lower ball joints are worn and sway bay links in dose not seem too be the power steering it turns fine and is full of fluid and why do u have too replace the entire lower controll arm if the lower boot is worn