It is possible to find in international court decisions
some general principles of law, among which are:
• good faith,
• obligation to make reparation,
• res judiciata (a matter may not, generally, be
relitigated once it has been judged on the merits),
• estoppel (the requirement of consistency in legal
argumentation), proportionality,
• lex specialis derogate legi generali (special law should prevail over general law),
• lex posterior derogate legi priori (more recent law prevails over an inconsistent earlier law),
• fair trial,
• liability for fault, and
• exhaustion of local remedies.

The correct answer is B.