to pigeonhole something is to conveniently place it in a category or genre so as to make it easier to describe.

[ ] A. Logrolling

[ ] B. Quid Pro Quo

[ ] C. Pigeonholing

[X] D. Lobbying

Pigeonhole means is not letting a bill pass through a committee onto the legislative floor.

When a congressional comittee pigeonholes a bill, the bill is ignored and forgotten.

The term "pigeonholing" is used to mean that a committee will ignore a pending bill by placing it aside, as if in a cubbyhole. The term comes from the small compartments used for domesticated pigeons when they are nesting.

Another modern synonym is to "bottle up" a bill in committee.

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