Which method of timekeeping is most accurate?

I searched for reliable sources of information to identify proper definitions of each one of the timekeeping methods. Once identified and clarified each, I compared the two through the prism of a human being on Earth. In practical terms, given the tools available to an average person.

Solar time is measured by Earth’s rotation relative to the Sun. Apparent solar time is measured by direct observation of the Sun or by a sundial. 

Sidereal time is measured by the apparent motion about the Earth of the distant stars.

A solar day is the time it takes for the Sun to return to the highest point in the sky from the day before. A sidereal day is how long it takes Earth to rotate so that distant stars appear in the same location from the night before. Therefore, a solar day is about 4 minutes longer than a sidereal day.

Standard time Is the time of a region or country that is established by law or general usage as civil time.

N/A.

Solar time is more accurate (out of solar and sidereal time) because a sidereal day is rarely the same length. It depends on the distance (angle) from Vernal Equinox.

https://study.com/academy/lesson/units-of-time-solar-sidereal-synodic.html

https://www.britannica.com/science/sidereal-time

https://www.britannica.com/science/solar-time

My general studies teacher, Ms. Lovell.

My principal, Mrs. Cameron.

My parents, Irina and Ben Be'eri.

My Capstone teacher, Shristy.