Why Is the Aldol Reaction Often Called an Aldol Condensation $\beta$

Why is the Aldol reaction often called an Aldol condensation?

A) The initially formed $\beta$ -hydroxy carbonyl compound loses a hydroxyl group.
B) The initially formed $\beta$ -hydroxy carbonyl compound loses an oxygen atom.
C) The initially formed $\beta$ -hydroxy carbonyl compound loses a hydrogen atom.
D) The initially formed $\beta$ -hydroxy carbonyl compound loses water.