单项选择题For a linear regression model with i.i.d. sample: , which assumption is not necessary for the consistency of the OLS estimator? A、 B、conditional homoskedasticity C、 for all D、None of the above conditions

单项选择题请指出下面模具图中序号10对应的零件名称。 A、导套 B、支承板 C、推板 D、动模座板