In the context of medical procedures involving insertion of instruments, the level of difficulty and complexity associated with each procedure can vary significantly. Let's evaluate each given option to determine which one is likely to be the most challenging:
Considering all options, a tracheostomy is the most invasive and complex procedure, often involving surgical intervention, making it the most challenging instrument insertion among those listed.
What is the management of the endoscopic finding given in the image?

Identify the ulcer:
The normal pH of arterial blood is:
Which enzyme is deficient in Gaucher’s disease?
Which of the following cranial nerves is responsible for the motor innervation of the muscles of mastication?
The anticoagulant effect of heparin is monitored using:
The causative agent of malaria is: