Okay, so how do i do it without an error? (Regex Literal Matching)

To match a literal question mark in regex, you need to escape it with a backslash, i.e., use '\?'. In C#, this should be written as '\\?' due to the additional escaping requirements.

When using Regex in C#, the string must take into account the language's escape sequences. Therefore, using '\\?' correctly represents the literal '?' character to the regex engine.

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