Which statement correctly describes what will happen when the half$-$cells are connected as shown in the following diagram?

a$)$ Current will flow for an instant and then stop due to the charge buildup in the two half$-$cells.

b$)$ Zinc ions will attract electrons from the copper electrode, and current will flow indefinitely.

c$)$ Current will not flow at all.

d$)$ Copper$($II$)$ ions will attract electrons from the zinc electrode, and current will flow indefinitely.