Legal maxim "the plaintiff himself is a wrongdoer" means that ...
Where the person bringing a legal action (the plaintiff) has engaged in wrongful or unlawful conduct related to the same matter for which they are seeking legal remedy.
Where the person bringing a legal action (the defendant) has engaged in wrongful or unlawful conduct related to the same matter for which they are seeking legal remedy.
Where the person bringing a legal action (the plaintiff) has not engaged in wrongful or unlawful conduct related to the same matter for which they are seeking legal remedy.
Where the person bringing a legal action (the defendant) has engaged in wrongful or unlawful conduct related to the same matter for which they are seeking legal remedy.
The legal maxim "the plaintiff himself is a wrongdoer" reflects a fundamental principle in law that deals with situations where the person bringing a legal action (the plaintiff) has engaged in wrongful or unlawful conduct related to the same matter for which they are seeking legal remedy. Hence, option (a) is correct.