Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:As mentioned above, TcPRAC enzymes contribute to delays in the effective host immune response by nonspecifically activating B-lymphocytes, thus enhancing the ability of the parasite to avoid immune clearance [8,9,11].
Category: