[单选题]
The diagram below shows ugt*wc ( c u/wy/.rs+la Daniel cell. Zinc is more reactive than copper. Wf ju ftals2c/)c82t r-hen the spontaneous reaction occurs, which statement aboutfs/ fca2t c8tlu j2)r- the Daniel cell is correct?
A. The mass of the copper electrode will decrease
B. Electrons flow from the copper electrode to the zinc electrode when the cell is operating
C. The blue colour of the copper (II) sulfate solution will fade over time
D. The zinc electrode is the cathode in this cell