Final answer:
Pathogenic fungi, parasites, and viruses can all be identified in sputum samples, so the correct answer is E. All of the above.
Step-by-step explanation:
The pathogenic organisms that can be identified in sputum samples include pathogenic fungi, pathogenic parasites, and pathogenic viruses. Therefore, the answer to the question is E. All of the above.
For instance, sputum samples can reveal Ascomycete fungi like Candida albicans, associated with respiratory infections. Moreover, parasitic infections such as those caused by Plasmodium undergo antigenic variation, which could also be spotted in sputum in certain cases. Furthermore, the detection of specific viruses is possible through tests like EIA, RT-PCR, PCR, which can also be applied to sputum samples to identify viral pathogens responsible for respiratory illnesses like Mycoplasma pneumoniae, the causative agent of 'walking pneumonia'.