Constitutional symptoms with lymphadenopathy, a very high WBC and thrombocytopenia fit an acute leukaemia. Of the options given, that is ALL: painless lymphadenopathy and thrombocytopenia are listed features.

• CML typically shows thrombocytosis, and lymphadenopathy is not typical in chronic-phase CML.
• A leukaemoid reaction is a reactive leukocytosis due to infection and would not explain marrow failure (low platelets) with nodes.