If government investigates only its critics for tax matters and leaves supporters in similar cases, what is the problem?

Correct answer: Selective law use and pressure on rights

Direct answer: Option C, selective law use and pressure on rights. The rule of law requires similar cases to be treated by the same legal standards, regardless of political support. Here the government investigates critics but ignores supporters in similar tax situations. Step by step: the cases are similar; treatment is different; the difference is political loyalty rather than a lawful reason; state power is therefore being used selectively. Such action can intimidate critics and indirectly suppress speech and political freedom. Option A, regular elections, is not the main issue because the example concerns unequal law enforcement. Option B, voting secrecy, concerns private ballots and is unrelated. Option C exactly describes selective enforcement and pressure on rights. Option D, voter identity, has no connection. Memory cue: same facts plus different treatment for political reasons means selective law enforcement.