Choose or find odd word - Rival , Spouse , Partner , Colleague , Companion

A. RIVAL

Choose or find odd word - Ballot , Manifesto , Election , Vote

C. ELECTION

Choose or find odd number - 6 , 12 , 18 , 9 , 7

E. 7

Choose or find odd word - Potassium , Silicon , Zirconium , Gallium , Germanium

A. POTASSIUM

Choose or find odd letter group - PQO , AtB , SIM , mnZ , DfE

D. MNZ