Please choose the correct ending to complete the given sentence: Health: [header] How to treat a fungal infection of the sinus cavity [title] Track the progress of the fungus. [step] Aspergillus fungi will first infect the paranasal sinuses and airways. It may then progress down into the lung tissue, or remain in the sinuses.

Ending1: If the infection continues into the lining of the mouth, it might result in nose bleeds and difficulty swallowing. [title] Examine the nasal cavity to get a sense of where the infection should originate. Ending2: It can also drip down the lung tissues. [title] Get your sample taken at a laboratory. Ending3: If you first suspect an infection, you should see your doctor. Other telltale signs of fungal infection in a sinus cavity are : [substeps] A decreased lung capacity that restricts oxygen flow to the throat. Ending4: At this time, the fungi will form a fungus ball, or aspergilloma, which is the hallmark of this infection. [substeps] A fungus ball is a mass of fungi that form together.

Answer format: ending1/ending2/ending3/ending4