Concept:The New Covenant is spiritual, made effective through the Holy Spirit.Explanation:In the New Covenant, God promised to write His law on the hearts of believers and put His Spirit within them.Paul describes believers as ministers of the New Covenant, “not of the letter but of the Spirit” (2 Corinthians 3:6).Believers become partakers of this covenant through the gift of the Holy Spirit, not through rituals or human obedience alone.Answer:C. the gift of the Spirit