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:populations due to the resultant increase in the availability of suitable benthic habitats for polyp proliferation (Duarte et al., 2012; Purcell, 2012; Makabe et al., 2014).
Category: