A political party receives large cash donations from various individuals without bank transfers. An investigation suggests the donations may be proceeds of crime from electoral offence violations. Under PMLA, which statements are correct? Statement 1: Political parties cannot be investigated under PMLA. Statement 2: If donations are proceeds of electoral violations (scheduled offences), they become liable for attachment. Statement 3: The political party must prove the donations were from legitimate sources. Statement 4: Proceeds of crime received for political purposes are exempt from PMLA. Which statements are correct?