The correct answer is option 1: 23 hrs. 56 min. 4.9 sec. This is also known as a sidereal day, which is the time it takes for the Earth to complete one rotation in relation to the stars.
Option 2: 23 hrs. 10 min. 2 sec is incorrect. This is not the correct time for one rotation of the Earth.
Option 3: 23 hrs. 30 min. is incorrect. This is also not the correct time for one rotation of the Earth.
Option 4: 24 hrs. is incorrect. This is the time it takes for the Earth to complete a solar day, which is the time it takes for the Sun to appear in the same position in the sky. It is longer than the sidereal day because the Earth has also moved in its orbit around the Sun during this time.
Therefore, option 1 is the correct answer.