Answer: Naive immoralist
Explanation: A naive immoralist is a manager of a foreign firm who doesn't adhere to ethical norms, because the manager sees other multinational firms not adhering to ethical practices of that host nation.
The British firm is a naive immoralist as the manager's reason for dumping untreated chemical waste into water in China, is because this manager has witnessed the French and American firms also do the same. This is unethical on all the firms part as they believe that their moral actions must be controlled by their consequences.