Final answer:
Barium (Ba) has 56 protons in its nucleus as indicated by its atomic number on the periodic table.
Step-by-step explanation:
The element Barium (Ba) has an atomic number corresponding to the number of protons in its nucleus. Using the periodic table, we can determine that Barium has an atomic number of 56.
Therefore, the correct answer to how many protons are in Ba is 56 protons (option b).