Answer:
a. Rules can be evaluated when records are created or edited.
d. Rule actions can take place immediately or on a specific date.
Explanation:
Workflow in Salesforce enable users to automate standard internal procedures and processes to save time across the business by using the workflow rule.
A workflow rule is a set of workflow instructions using the if/then statement syntax.
An administrator should consider the following when configuring workflow rules;
1. Rules can be evaluated when records are created or edited: in this case, the criteria that affects the running of a rule and the consequent actions to be executed when there's a match are defined herein. This simply means that, once a rule is created or edited and it meets or matches with the criteria, the rule would run no matter what.
2. Rule actions can take place immediately or on a specific date: time triggers are used for time dependent rules. This simply means that, the rule would run at the specified time.
Basically, the workflow rule in Salesforce can be used to perform various tasks, such as sending an email, updating fields etc.