After the Amalgamation of Satellite Sounds Ltd

After the amalgamation of Satellite Sounds Ltd.with RMK Broadcasting Inc.,human resource managers were assigned the task of changing job duties and reassigning responsibilities among the amalgamated workforce.What is the source of the employer's ability to effect changes of this nature without incurring liability to the amalgamated employees?

A) the recital of management rights in employment contracts
B) company policies or reference to the employee policy manual
C) the employer's right to define the description of the work to be performed
D) the employer's defined ownership of intellectual property