(I know this is late so hopefully other people find it helpful)
<u>Answer</u>: Solid Cu
Since this is a <u>voltaic cell</u>:
<u>Copper</u> is the cathode, therefore having a positive charge.
<u>Zinc</u> is the anode, therefore having a negative charge.
(Also, I took the exam and it's correct; good luck everyone!)
