Words given on the left side of (::) are related with each other by some Logic/Rule /Relation. Select the missing word/word pair on the right side of (::) from the given alternatives based on the same Logic/Rule/Relation.

Soldiers : Army :: ?

Cattle : Herd

Soldiers : Army :: ?

The logic followed here is :

Soldiers are part of Army

Similarly

Cattle : Herd

Cattle is part of herd