The correct answer is: Universal.
Something that relates to everyone in the world is universal. This means that it is something that applies to all people, regardless of their race, religion, nationality, or any other characteristic. Some examples of universal things include the need for food, water, and shelter; the desire for love and belonging; and the fear of death.
The other options are not as accurate. General can refer to something that is common or widespread, but it does not necessarily mean that it applies to everyone. Common is similar to general, but it can also refer to something that is ordinary or unremarkable. Usual is similar to common, but it can also refer to something that is habitual or customary.
In conclusion, the correct answer to the question “Something that relates to everyone in the world” is universal.