Which of the following formats can Apex script be written in?

Apex script can be written primarily in the form of classes and triggers. Classes define reusable components that encapsulate logic and can include methods, while triggers are specific types of Apex code that execute in response to particular events in Salesforce, such as when records are created, updated, or deleted. This structure allows developers to create robust applications that utilize Salesforce's database and business logic effectively.

Using classes and triggers facilitates adherence to object-oriented programming principles, promoting organized and maintainable code. This dual structure supports both the handling of bulk operations through triggers, which can invoke class methods for processing, and the encapsulation of business logic within class methods, contributing to modular design.

Other proposed formats, such as functions and variables or objects and records, do not accurately represent the foundational way Apex code is structured. While functions and variables are indeed part of Apex, they do not encompass the broader architectural design necessary for effective development within the Salesforce platform.