37歲孕婦，G1P0，妊娠39週，生產後如圖所示：
下列四者中最可能的診斷為何？
(A)first-degree laceration
(B)second-degree laceration
(C)third-degree laceration
(D)fourth-degree laceration
承上題，正在縫合的組織為何？
vaginal mucosa
vaginal submucosa
anal sphincter
rectal mucosa
