a) Compulsory voting means all eligible
citizens are required to vote in elections (e.g. Australia). Optional voting means all eligible citizens are allowed to
vote in elections, but aren't required to (e.g. USA).
b)b) “Two Party Systems” (e.g. the USA) are
political systems where two large political parties dominate the country’s
political system. “Multi-Party Systems” (e.g. many countries in Europe) are political
systems there many, smaller parties exist, and often have to work in coalitions
to form government.
c0) In Australia, the major party candidates for each electorate are typically chosen by the local branch of the respective major political party. However, the practice of "parachuting in" candidates occurs when the party leadership overrides this process, appointing a candidate to run in a specific electorate instead of deferring to the local branch's choice. Notable instances of this include the selections of Kristina Keneally in Fowler and Andrew Charlton in Parramatta.
c)