[正答]
C
※国試ナビ4※ [109I018]←[国試_109]→[109I020]
[★]
B
※国試ナビ4※ [109I019]←[国試_109]→[109I021]
※国試ナビ4※ [109I017]←[国試_109]→[109I019]
.