What is democracy and why democracy?

Here is some information about four countries. Based on this information, how would you classify each of these countries. Write ‘democratic’, ‘undemocratic’ or ‘not sure’ against each of these.
a Country P: The parliament cannot pass a law about the army without the consent of the Chief of Army.
b Country Q: The parliament cannot pass a law reducing the powers of the judiciary.
c Country R: The country’s leaders cannot sign any treaty with another country without taking permission from its neighbouring country.
d CountryS: All the major economic decisions about the country are taken by officials of the central bank which the ministers cannotc change.