A 7-year-old child with rheumatic heart disease presents with pallor, fever and a palpable spleen. The following investigations would be needed to arrive at a diagnosis except:

a. Electrocardiogram(Ref: Nelson's 20/e p 2269-2271, Ghai 8/e p 433-443)Infective endocarditis should be suspected in presence of pallor, fever and splenomegaly in a known case of RHDUrine examination shows albuminuria and microscopic hematuriaBlood culture should be done for diagnosis of the causative agentEchocardiography is done to detect the cardiac changes like vegetations.