Final answer:
The plebeians revolts led to the creation of the Twelve Tables, ancient Rome's first written code of laws, around 451 BCE, to ensure fairness in legal proceedings.
Step-by-step explanation:
The historical event that directly led to the creation of a written code of laws in ancient Rome was (a) The plebeians revolts. The plebeians, concerned about the unequal legal judgements that favored the patricians, demanded that laws be documented and made publicly accessible. This resulted in the formulation of the Twelve Tables around 451 BCE, the first set of written laws in Rome, which embodied the laws that governed both private and public life. This act significantly reduced the likelihood of corruption in legal proceedings and marked a critical development in the legal tradition that would influence future European legal systems.