_________________ such a strange man.

The statement "I have seldom come across such a strange man" is correct because the phrase "come across" is commonly used to mean to encounter or meet someone or something unexpectedly. It conveys the idea of finding or discovering someone or something in a more casual or accidental context, which fits well with the description of a person being "strange." This phrasing captures the nuance of encountering a peculiar individual without suggesting a deeper or more intentional interaction.

The other options do not convey the same meaning or context effectively. For example, "met" implies a more formal introduction rather than a casual encounter, while "recognized" suggests familiarity or identification, which doesn't fit with describing someone as strange. "Found," on the other hand, can imply a more active search or a discovery, which might not align with the nature of the encounter described in the context. Therefore, "come across" effectively delivers the intended sentiment of a casual meeting with an unusual person.