Answer:
A) 6
Step-by-step explanation:
The number of protons is the defining characteristic of an element. This means that a carbon atom has always 6 protons.
Isotopes are atoms of the same element, equal number of protons, and different number of neutrons.
The carbon-12 atom has 6 protons and 6 neutrons.
The carbon-14 atom has 6 protons and 8 neutrons.