B and C
about D, while recommended, system.assert isnt required to pass through coverage

I think the answer is C, D. Triggers must have at least 1% code coverage.

B & C is correct:
When implementing changes from the sandbox into production, consider the following:

C. At least 75% of Apex code must be covered by unit tests.

At Salesforce, there is a requirement that at least 75% of Apex code must be covered by unit tests before deployment to production. This is a key requirement to make sure the code works as expected and to minimize the risk of bugs in production.

B. All triggers must have at least one line of test coverage.

All Apex triggers must have at least minimal test coverage, meaning that each line of code in the trigger should be run at least once during unit testing. Although the total Apex test coverage must be 75%, each individual trigger must have at least one line of code covered by testing.
Other options:

A. Should deploy during business hours to ensure feedback can be Quickly addressed: Deploying during business hours can be risky, as potential problems can affect business operations. Usually deployments are done outside business hours to minimize the impact on users.
D. Unit tests must have calls to the System.assert method: While System.assert is recommended to verify test results, it is not a requirement for production deployment. It is more important to cover the code with tests and meet other quality requirements....

C & D