How does a federal system differ from a unitary system?
A. In a federal system, power is concentrated at the regional level. In a unitary system, the national government shares power with the regional governments.
B. In a federal system, the national government shares power with the regional governments. In a unitary system, power is concentrated at the national level.
C. In a federal system, the national government shares power with the regional governments. In a unitary system, power is concentrated at the regional level.
D. In a federal system, power is concentrated at the national level. In a unitary system, the national government shares power with the regional governments.

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