下列关于DNA分子的叙述中，错误的是[ ]

A．磷酸和脱氧核糖交替连接构成了DNA分子的基本骨架

B．DNA分子碱基对的排列顺序千变万化构成了DNA分子的多样性

C．双链DNA分子中，A=T，C=G，(A+G)/(T+C)=1

D．DNA复制时，必须先解旋为两条单链

My friend asked me _______. 　　[ ]

A. if I will come to the party

B. that he would help me to clean the room 　　

C. what was wrong with me

D. how should he do it next