What is how many ghosts in a christmas carol?

In Charles Dickens' A Christmas Carol, there are four prominent ghosts:

• The ghost of <a href="https://www.wikiwhat.page/kavramlar/Jacob%20Marley">Jacob Marley</a>, Scrooge's former business partner.
• The <a href="https://www.wikiwhat.page/kavramlar/Ghost%20of%20Christmas%20Past">Ghost of Christmas Past</a>, who shows Scrooge scenes from his earlier life.
• The <a href="https://www.wikiwhat.page/kavramlar/Ghost%20of%20Christmas%20Present">Ghost of Christmas Present</a>, who reveals the current state of Christmas celebrations.
• The <a href="https://www.wikiwhat.page/kavramlar/Ghost%20of%20Christmas%20Yet%20to%20Come">Ghost of Christmas Yet to Come</a> (also known as the Ghost of Christmas Future), who presents a grim vision of what will happen if Scrooge doesn't change.

Marley's ghost is the one who warns Scrooge about the three spirits and the importance of changing his ways.