This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Medicine
Investigations in a clinically suspected case of tuberculosis 
Select and explain. 
A. Mantoux (in children), B. Sputum AFB, C. PCR, D. All
D: All
Answer: D: All 
Explanation: The diagnostic procedures in a clinically suspected case of TB include AFB microscopy of sputum using Ziehl-Neelsen basic fuschsin stain;Mycobacterium culture using Lowenstein-Jensen or Middlebrook medium;nucleic acid amplifications using PCR,BACTEC;radiographic procedures like chest X ray with classic picture of upper-lobe disease with infiltrates & cavities,CT;Tuberculin skin testing with purified protein derivative which is a screening for latent M.tuberculosis infection Reference:Harrison's Medicine-18th edition,page no:1350,1351.