The correct option is A voluntary conciliation
Conciliation is one of the non binding procedures where an impartial third party, known as the conciliator, assist the parties to a dispute in reaching a mutually agreed settlement of the dispute. As per Part III of the act, the process of conciliation extends whether contractual or not. But the disputes must arise out of the legal relationship. It means that the dispute must be such as to give one party the right to sue and to the other party the liability to be sued. But Part III of the Act does not apply to such disputes as cannot be submitted to conciliation by the virtue of any law for the time being in force. This shows the importance of voluntary conciliation.