According to Paul, just as the law came to increase trespass, so sin came to increase
Paul in his letter to the Romans 5:20 states that "Now the law came in to increase the trespass, but where sin increased, grace abounded all the more." Here, Paul explains that just as the law made the knowledge of sin greater, the sin increased in response. However, despite the increase in sin, grace, which is the undeserved love and favor of God, abounds all the more. In other words, the more sin there is, the more God's grace is able to overcome it. Therefore, the answer is "grace".