Based on the following replication bubble, which of these statements is true?

◦ X and Y are leading strands, W and Z are lagging strands
◦ X and Z are leading strands, W and Y are lagging strands
◦ X and W are leading strands, Y and Z are lagging strands
◦ W and Z are leading strands, X and Y are lagging strands
◦ W and Y are leading strands, X and Z are lagging strands