Determining the design approach

You are building a shopping cart for your application. When doing so, you have designed the following request code for the endpoint /abc.

POST /abc
{
 "abc-request": [
 {
 "method": "POST",
 "path": "/customer",
 "ref": "newcustomer",
 "body": {"name": "Tony Stark"}
 },
 {
 "method": "POST",
 "path": "/order",
 "ref": "neworder",
 "body": {"customer": "@{newcustomer.id}"}
 }
 ]
}

What can be said about the design approach used in the given scenario?

Options

1. You are using the Resource modeling design approach
2. You are using the Separation of concerns design approach
3. You are using the Composite API design approach
4. None of these