Final answer:
The Eighth Amendment prohibits cruel and unusual punishment, making torture, execution, and electrocution illegal punishments. Solitary confinement may or may not be considered illegal depending on its conditions and duration.
Step-by-step explanation:
Answer:
The illegal punishment according to the Eighth Amendment is cruel and unusual punishment. This means that punishment should not be excessively harsh, disproportionate to the crime committed, or cause unnecessary pain or suffering. In the context of the options given, torture, execution, and electrocution are all considered illegal punishments under the Eighth Amendment. In contrast, solitary confinement is not inherently considered illegal under the Eighth Amendment, but its specific conditions and duration could be subject to scrutiny.
Learn more about Eighth Amendment and illegal punishments