Final answer:
Hydrocarbons are the most likely cause of Julia's occupational disease involving the central nervous system, as they can lead to central nervous system toxicity when exposure occurs in the workplace.
Step-by-step explanation:
If Julia has developed a work-related occupational disease involving the central nervous system, the organic compound most likely to be the cause is hydrocarbons. Exposure to certain hydrocarbons, which are present in various industrial and chemical solvents, can lead to central nervous system toxicity. Symptoms of such exposure can include headaches, dizziness, confusion, and neuropathy. It is essential for workplaces dealing with these compounds to have proper safety procedures in place to protect their employees from potential health hazards.