--- I can’t afford the white sweater. Can you show me another one?

--- What about the orange one? The price is a little ________.

A．cheaper

B．higher

C．lower

D．more expensive

用离子选择电极法测定血电解质，可用下列哪种抗凝剂（）

A.EDTA-Na₂

B.EDTA-K₂

C.肝素锂

D.肝素钠

E.肝素钾