Concept:Hadith reliability is graded into accepted and rejected categories.Explanation:The recognised degrees of Hadith authenticity include Sahih (authentic), Hasan (good), and Da′if (weak).However, "Mundasil" (or Munfasil) is not a degree of reliability.It only describes a Hadith whose chain of narrators is disconnected or broken.Thus it is a condition affecting classification rather than a separate grade.Answer:B. Mundasil