question: What protection could not be applied to LaserDiscs , making them prone to piracy ?
answer: Macrovision 's Copyguard protection
turker_answer: Macrovision 's Copyguard protection could not be applied to LaserDiscs , making them prone to piracy .
rule-based: Could not be applied Macrovision 's Copyguard protection to LaserDiscs , making them prone to piracy .