[单选题]
When the first law oxid;ap +,lvnti;y+ h ds/yrp7* nsa+6f/bl8 nhp,gyye3+s /+dymrt4 (rnj8wf thermodynamics, $Q = \Delta U + W$, 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