Answer:
True
Step-by-step explanation:
API is application programming interface. APIs allow communication between applications/programs: they are basically "outside" data that can be accessed by an application by using it's code(example, how I may access go*gle fonts using it's API attached to my html stylesheet link).
The source is the code itself. Source code is the set of instructions that makes any program or application do whatever they do. An API is defined and works based on its source code.