Healthy study habits are best described as
physical and emotional strategies that help a student learn more effectively.
the way a student spends most of the time focusing totally on schoolwork.
prioritizing a student’s comfort and convenience above everything else.
a student’s ability to think clearly and focus on assignments more effectively.

Healthy study habits are aimed to increase student's efficiency, by setting and distributing specific schedules, that allow them to study enough and have time to rest or do recreational activities which is also important, because the major importance here is to stay focus during studying hours, it's not more hours, it's about a better quality of them.

So, to achieve the effectiveness, students most set physical and emotional goals too, like dedicating specific hours to study, then to exercise and recreate in other activities that they like, this way the study will be less tough and more enjoyable.

There are several things students can do to develop study habits as:

Be organized with schedules and that type of things. There is time to study and to rest.
Set goals. Having expectations can make the student hungry enough to maintain focus and motivated.
Be positive.
Have a plan. Find the right way to learn, knowing yourself.
Study actively, this means that passiveness shouldn't be considered during study time, otherwise students won't be focus enough.

Therefore, the right answer is the first one.