A) This choice is incorrect because unexplained weight gain is not a common symptom of leukemia. Weight loss may be more typical in some cases.

B) This choice is correct. Easy bruising and bleeding are common manifestations of leukemia due to a decreased number of healthy blood cells and platelets, which are responsible for clotting.

C) This choice is correct. Persistent fatigue and weakness are common symptoms of leukemia. Leukemia can lead to a decrease in normal blood cells, causing anemia and leading to fatigue and weakness.

D) This choice is correct. Leukemia can weaken the immune system, making the person more susceptible to infections, leading to frequent infections and fever.

E) This choice is correct. Leukemia can cause the enlargement of lymph nodes, leading to painful and swollen lymph nodes.