Which of the following is not a duty of works committee under the Industrial Disputes Act?

To promote measures for securing and preserving amity and good relations between the employees and workmen.

To form groups among workmen and strengthen mediation between employer and employee.

To achieve the object, it is their duty to comment upon matter of common interest or concern of employers and workmen.

To endeavour to compose any material difference of opinion in respect of matters of common interest or concern between employers and workmen.