煤岩体的物理力学性质参数包括（）

A、单轴抗拉强度

B、单轴抗压强度

C、真密度

D、煤自燃

Which of the following statements is least accurate()

A. Futures contracts are easier to offset than forward contracts. 

B. Forward contracts are generally more liquid than futures contracts. 

C. Forward contracts are easier to tailor to specific needs than futures contracts.