The correct options are
B Defection causes instability in the government.
D A legislator can be disqualified if he votes against his party orders.
Defection is the act of leaving a political party to join another one. Legislators ‘defecting’ from their parties, causes a lot of instability in the government. Anti-Defection Law was passed in 1985. The legislators can be disqualified if they abstain from voting despite party orders to vote in a certain way or if they cast a vote that goes against their party’s orders.