Explanation:

- Collective Bargaining

- This involves discussions and negotiations between employers and employee representatives.

- It aims to reach agreements that regulate working conditions.

- Discipline Procedure

- A formal process for identifying and addressing employee misconduct.

- Ensures fairness and consistency in handling disciplinary issues.

- Grievance Redressal Machinery

- A systematic approach to resolve employee complaints.

- Helps maintain a peaceful work environment by addressing worker concerns.

? Option 4: All of the above is the correct answer. All these methods are part of the Industrial Relations System.