— He didn’t come to school yesterday, did he ?

— _________.He was ill in bed.

A．Yes, he did

B．No, he didn’t

C．Yes, what a pity

D．No, I think

珠江—西江经济带发展规划探索建立（）等机制，建立吸引社会资本投入生态环境保护的市场化机制，推行环境污染第三方治理。

A、生态补偿

B、水权交易

C、碳排放权交易

D、排污权有偿使用和交易