Answer:
True
Step-by-step explanation:
Ethics is not only important to create a project culture, it is always important. Unethical behavior is simply wrong, and eventually those who behave unethically pay the price for their bad behavior, e.g. get fired, their organization suffers or fails completely, their lives are a mess, etc.
When the project sponsor and the project manager are trying to build a project culture, ethics is central in order to determine how people should act in the best interest of the project itself, the project's team, and the project's stakeholders. Good ethics result in better work and higher efficiency resulting in the best project within the team's possibilities.