Final answer:
An SRC, or Silicon Controlled Rectifier, is made from adjoining layers of semiconductor material at the junction; this is essential for its function as a rectifying device in power control.
Step-by-step explanation:
An SRC, or Silicon Controlled Rectifier, is a three-terminal device used predominantly in power control and switching applications within the field of electronics and electrical engineering. Constructed from semiconductor material, an SRC operates by forming a p-n junction which is essentially the interface between the two semiconductor materials of opposite type (n-type and p-type). In the context of the options provided with the question, the correct answer is c. Junction. This is because the SRC functions on the principle of junction formation that allows for its rectifying (current control) capabilities.