关于物体的内能，下列说法中错误的是：

A．物体的内能是不能改变的

B．热传递可以改变物体的内能

C．做功可以改变物体的内能

D．内能是物体所有分子动能和分子势能的总和

—Could you give us an account about the big fire?

—OK. It was a Friday evening _______the fire broke out and ten persons were killed in it.   

A．where

B．on which

C．that

D．when