But House would not have been able to know that without A, looking at his toe and confirming that he has an onychomycosis, which is a toenail fungus, and B, that this is, in fact, fungal spores.

但是如果 A 没有检查他的脚趾并确认他患有甲癣，那是一种趾甲真菌，而 B 则无法知道这实际上是真菌孢子。