The subject "Either who or he" is treated as singular because "either...or" joins two singular elements.The verb "is" matches the singular subject — "is" is used for singular subjects
Either who or he ______ at fault.
Review the verified answer and explanation for this ASF Airports Security Force past-paper question on CampusFin.
Question context
This question is part of 🗣️ Verbal Ability within the broader 🧠 Aptitude Mastery subject and appears in the ASF Airports Security Force preparation collection. Reviewing the answer together with nearby questions helps reinforce the underlying concept and identify how it may appear in competitive exams.