某化工企业生产流程示意图如图所示，下列说法中正确的是（     ）

A．钛酸亚铁（FeTiO₃）中钛元素为+3价

B．① 中反应：2FeTiO₃＋6C＋7Cl₂一定条件2X＋2TiCl₄＋6CO，则X为FeCl₃

C．② 中反应说明金属钛比金属镁的化学性质活泼，氩气起保护气的作用。

D．③中反应要使原料全部转化为甲醇，理论上CO和H₂投料的质量比是7：1

Such an inspiring speech ________ at the graduation ceremony that every one of us was deeply moved and strongly encouraged.

A．did he make

B．he made

C．had he made

D．he had made