SelectGraphs is an option for OneLoopSum indicating that only a slected set of graphs of the list provided to OneLoopSum is to be calculated. Possible settings are: SelectGraphs -> {i, j, ...} or SelectGraphs -> {a, {b, c}, ...} which indicates the graphs to be taken from the list provided to OneLoopSum. In the second setting the list {b, c} indicates that all amplitudes from b to c should be taken.