Answer: The correct answer is "a. computer-aided design (CAD)".
Step-by-step explanation:
Computer-aided design (CAD) is the use of computer technology to design and document products and systems. CAD software allows engineers and designers to create, modify, and optimize parts and products in a virtual environment, without the need for physical prototypes. It is widely used in various fields such as architecture, mechanical engineering, electrical engineering, and many more. CAD software can also simulate the performance of a product, allowing designers to test and optimize it before it is manufactured.