Oxygen’s atomic number is 8. this means that an oxygen atom has
a. eight neutrons in its nucleus.
c. eight protons in its nucleus.
b. a total of eight protons and neutrons.
d. a total of eight neutrons and electrons.

The correct choice is

c. eight protons in its nucleus.

we know that the atomic number of an element determines the number of electrons and number of protons in the nucleus of atom of the element. In an element, the number of electrons and number of protons are equal and is same as the atomic number of the element.

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of carbon is as shown here in the image.

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)