This defines money assigned for a particular use:

a.

Extradites

c.

Precedent

b.

Appropriates

d.

Doctrine

B. Appropriates is what defines money assigned for a particular use. To assign money to a particular use is to appropriate.

I think the correct answer from the choices listed above is option B. Appropriates defines money assigned for a particular use. The government does appropriations during budgeting sessions. This is to ensure that all their projects have sufficient amount to achieve its completion.