Does this "should" mean "obligation" or "presumption"? I think the latter.
24)While most experts say eight hours of sleep is ideal, the truth is it all depends on how you feel. Some people do well with seven hours or less, while others require nine or more to be at their best. If you are ill or under tremendous stress, you will probably need to sleep longer than you usually do. The best indicator of how much sleep you need should be based on how you feel. Keep in mind that sometimes we fool
ourselves into thinking that we’re getting enough sleep. If you are getting sufficient sleep, you should feel refreshed and not have trouble getting out of bed in the morning.
I also thought like you did(2), but this is a national question, and the answer went for 1. which I feel a regret.
If the national test said it meant that you are obliged to feel refreshed, the test is wrong.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.