Which work group member has the responsibility of demonstrating to a jury that a defendant is guilty beyond a reasonable doubt

The prosecutor is a legal representative of the prosecution, or the accusation, in most countries. Specially those with a common law adversarial system, or at least the civil law inquisitorial system. The prosecutors are the ones responsible for presenting the case in a criminal trial against the individual who is being accused of breaking the law. The correct answer is:

The prosecutor