正解:A
An NDA, or non-disclosure agreement, is a legal contract that binds an employee to keep certain information confidential and not share it with unauthorized parties. This information may include trade secrets, intellectual property, business strategies, customer data, or other sensitive or proprietary information that gives the company a competitive advantage. An NDA protects the company's interests and prevents the employee from disclosing or using the information for personal gain or malicious purposes1.
Reference
1 - 10 Types of Employment Contracts | Indeed.com