OOPs and Database using Apex

What is the primary purpose of encapsulation in Apex?

• To define a blueprint for creating objects.

• To allow a class to inherit properties from multiple classes.

• To hide the internal state of an object and restrict direct access to it, exposing only necessary functionality.

• To provide different implementations for a method in different classes.

Which DML operation is used to update existing records in Salesforce?

• update

• upsert

• delete

• insert

In Apex, if Animal is an abstract class and Dog extends Animal, which statement accurately describes polymorphism when working with these classes?

• Polymorphism is primarily achieved through static methods in both Animal and Dog.

• A Dog object can be assigned to an Animal variable, allowing calls to common methods defined in Animal.

• The Dog class must override all non-abstract methods from the Animal class.

• An Animal object can be directly instantiated and used without defining specific animal types.

Which Apex collection type guarantees unique elements and does not maintain insertion order?

• Array

• List

• Map

• Set

In Apex, what will be the output of the following code snippet?

• Second

• Third

• Error

• First

What's the output of this code snippet?

• From A From B

• From B From A

• From A From A

• From B From B