[名词解释] 单卵双胎

解释图中B现象 男，6岁，身材矮小，关节畸形，血钙磷化验异常，如图，最可能的诊断为() ["A．坏血病","B．肾性佝偻病","C．粘多糖病","D．克汀病","E．脂质沉积病"] 死产(stillbirth) 双胎妊娠(twin pregnancy) 男，8岁，外伤后入院。结合图片，最可能的诊断是() ["A．Colles骨折","B．右肱骨髁上骨折","C．Smith骨折","D．孟氏骨折","E．青枝骨折"] 单卵双胎