The BEST definition of a parliamentary form of government is "a system of government in which executive power is held by a member of the legislature."
The history of the Parliamentary system can be traced to the United Kingdom.
In a Parliamentary system, the Prime Minister or Chief Executive is selected or elected by the members of the Parliament and he is also a member of the parliament, including other officials that would make up the executives.
It is the duty of the Prime Miniter to appoint from the parliament to make up his executives or cabinet.
Hence, in this case, the correct answer is option A"a system of government in which executive power is held by a member of the legislature"
