Ensure Field Value Entry

B.

To ensure that a value is entered in a field, you can use validation rules. Validation rules are used to enforce business logic and data quality standards by verifying that the data entered by users meets certain criteria. If the data entered by a user does not meet the criteria specified in the validation rule, the user will receive an error message and will not be able to save the record until the issue is resolved.

To create a validation rule to ensure that a value is entered in a field, follow these steps:

1. Go to Setup and select Object Manager.
2. Select the object you want to create the validation rule on.
3. Click on Validation Rules in the left-hand menu.
4. Click on New Rule.
5. Give your validation rule a Name and Description.
6. Choose the appropriate criteria to trigger the validation rule. In this case, you would select "Formula evaluates to true."
7. Enter the formula that will validate that a value is entered in the field. For example, if you want to ensure that a value is entered in the "Name" field, you could use the following formula: ISBLANK(Name).
8. Add an Error Message to display to the user if the validation rule fails.
9. Save the validation rule.

Once you have created the validation rule, any time a user attempts to save a record without entering a value in the specified field, they will receive the error message you defined and will be prevented from saving the record until the issue is resolved. This ensures that data quality standards are maintained and helps to prevent errors and inaccuracies in your data.

Therefore, out of the given options, none of them are correct. Field level security is used to control access to fields based on the user's profile, setting a property in page layout would not help enforce data validation rules, creating a lookup field is not relevant to ensuring that a value is entered in a field, and defining picklist values would not ensure that a value is entered in a field.