Our teachers often suggest we ______ take it easy when facing any difficulty.

A．had

B．could

C．would

D．should

Ⅱa型高脂蛋白血症的血清检测特点是

A．血清透明，胆固醇明显增加，甘油三酯正常

B．血清乳白色，胆固醇正常或稍高，甘油三酯明显增加

C．血清混浊，胆固醇稍高，甘油三酯增高

D．血清混浊，胆固醇正常，甘油三酯稍高

E．血清透明，胆固醇明显增加，甘油三酯稍高