[单选题]
When the first law of thermodynamicn6*ly0k0xbxeu9 obk7oq al3- sri4o rw3f d9x ec6pqw- b7-r8e, $Q = \Delta U + W$, is applied to an ideal gas that is taken through an isothermal process,
A. $\Delta U = 0$
B. $W = 0$
C. $Q = 0$
D. none of the above
