Question: Wani masanin kimiyya yana binciken dalilin da yasa yawancin kifaye da aka kama daga rafin gida suka nuna irin wannan maye gurbi. Ya gano cewa zafin ruwan kogin ya yi tashin gwauron zabi tun lokacin da wata masana'anta ta fara zubar da ruwan zafi a cikin rafin. Masanin kimiyyar ya kammala da cewa ƙaruwar zafin ruwa a lokacin ƙwai ya haifar da maye gurbi a cikin kifi. Bisa ga wannan bincike, maye gurbi ya faru ne a dalilin 
Options:
rashin lafiyan autoimmune.
lahani na haihuwa.
yanayin muhalli.
rauni daga mafarauci.
Answer: C