A.1 B.2 C.4 D.8
A.1A,1B,1C,1D B.1A,1B,1D,1C C.1A,1C,1B,1D D.1A,1C,1D,1B
A.Sintrasearch<Sintersearch<SinterRATsearch; B.Sintrasearch>Sintersearch>SinterRATsearch; C.Sintersearch<Sintrasearch<SinterRATsearch; D.Sintersearch<SinterRATsearch<Sintrasearch;