What is democracy and why democracy?

Write a response to the following arguments against democracy:
a Army is the most disciplined and corruption-free organisation in the country. Therefore army should rule the country.
b Rule of the majority means the rule of ignorant people. What we need is the rule of the wise, even if they are in small numbers.
c If we want religious leaders to guide us in spiritual matters, why not invite them to guide us in politics as well. The country should be ruled by religious leaders.