Final answer:
Chemka is performing the role of a spokesperson, representing the company's decisions at a press conference, which is distinct from disseminator, monitor, liaison, or figurehead roles.
Step-by-step explanation:
Chemka is performing the role of a spokesperson. A spokesperson is responsible for communicating on behalf of the company to the public, which includes giving press conferences about important company news. In contrast to the disseminator role, which involves spreading information within the organization, or a monitor, who gathers information, the spokesperson's key function is to share information with external stakeholders. The liaison role involves communication between different organizations or parts of an organization, while the figurehead plays a more ceremonial role. Therefore, when speaking at a press conference to discuss closing branches, this is a typical spokesperson function.