Answer: they evaluate both "RELEVANT AND RESPONSIVE" factors.
Explanation: Source selection evaluation board, are those that helps organization to select contract proposal and the best proposal that meets the job requirements. They identify the job requirements and communicate those requirements.
They evaluate the relevant factor, by identifying the proposal that meets the job requirements, and the ones that is properly explained in accordance to companies ideology.
They evaluate the responsive factor by knowing the proposal that will be most acceptable by the company if communicated. In evaluation of the responsive factor, they consider the company's targeted aim, beyond the job requirements, to consider the best proposal to be accepted and appreciated, when communicated to the company.