Step 1: Understanding the question.
The city that was designed specifically for the motor age, taking into account automobiles and road transportation, is Radburn. It was designed with a focus on the automobile, separating pedestrians from cars.
Step 2: Analyzing the options.
(A) Welwyn: Welwyn was designed by Ebenezer Howard as a garden city concept, not for the motor age.
(B) Latchworth: Letchworth was also a garden city designed by Howard, focusing on a blend of urban and rural life, not specifically for automobiles.
(C) Chandigarh: Chandigarh, designed by Le Corbusier, is a modernist city but was not specifically designed for the motor age.
(D) Radburn: Correct — Radburn was specifically designed for the motor age, with roads designed for automobiles and pedestrians separated for safety.
Step 3: Conclusion.
The correct answer is (D) Radburn, as it was designed specifically with the motor age in mind.