Answer:
Karl Benz, a German inventor, is credited with inventing the motor car, option 'D' in the given options. He is often referred to as the "Father of the Automobile" because of his significant contributions to the development of the modern automobile.

The Invention of the Motor Car:
Karl Benz invented the motor car in 1885. His creation, which he called the Benz Patent-Motorwagen, was the world's first practical motor vehicle. It was a three-wheeled automobile powered by a gasoline-powered internal combustion engine. The motor car had a top speed of about 10 miles per hour and featured several innovative design elements, such as a lightweight tubular frame, a rear-mounted engine, and a differential gear system.

Contributions to the Automobile Industry:
Karl Benz's invention laid the foundation for the modern automobile industry and revolutionized transportation. His motor car design incorporated many elements that are still used in automobiles today. Some of his notable contributions include:

1. Internal Combustion Engine: Benz developed a gasoline-powered internal combustion engine that provided a reliable and efficient source of propulsion for the motor car. This engine design became the standard for automobiles and is still widely used today.

2. Patented Inventions: Benz obtained several patents for his innovative designs, including patents for the motor car and its components. These patents protected his inventions and allowed him to commercialize his designs.

3. Business Ventures: Benz founded the Benz Patent-Motorwagen company to produce and sell his motor cars. This marked the beginning of the automobile manufacturing industry. His business venture was successful, and it laid the groundwork for future automobile companies.

Legacy:
Karl Benz's invention of the motor car paved the way for the modern automobile industry. His innovative designs and engineering principles greatly influenced the development of automobiles in the years that followed. Today, his legacy lives on, and his contributions to the automobile industry are celebrated worldwide.