Consider the following example. An IP 12.35.68.30 is present. Here 12 is group A, 35 is group B, 68 is group C and 30 is group D. the C class is used to ensure that an IP originated from dissimilar host. Here, web hosting multiple IP is very beneficial. With web hosting multiple IP, 2 websites will not have the similar class c IP addresses. Therefore, they can help in improved rankings. If the class c IP hosting is dissimilar due to web hosting multiple IP addresses, it is counted as an immense link importance and you get a better ranking.