Choose or find odd pair of words - (Principal : School) , (Soldier : Barrack) , (Artist : Troupe) , (Singer : Chorus)

A. PRINCIPAL : SCHOOL

Choose or find odd letter group - ACEG , IKMO , TVWY , FHJL , NPRT

C. TVWY

Choose or find odd word - Polar bear , Reindeer , Yak , Silver fox , Leopard

E. LEOPARD

Choose or find odd number - 12, 25, 37, 49, 57

C. 37

Choose or find odd letter group - VTOJE , USNID , UPKEA , OMIDB

B. USNID