The Chhatrapati Shivaji Terminus (formerly Victoria Terminus) railway station in Mumbai was designed by which architect?

Introduction / Context:
This question is about the architectural history of one of India's most iconic railway stations, the Chhatrapati Shivaji Terminus (CST) in Mumbai, formerly called Victoria Terminus. The station is a UNESCO World Heritage Site and a prime example of Victorian Gothic Revival architecture in India. Knowing the architect who designed it is a part of general awareness about Indian heritage and colonial urban development.

Given Data / Assumptions:
- The station in question is Chhatrapati Shivaji Terminus in Mumbai.
- The options list four architects: Frederick William Stevens, Santiago Calatrava, Fazlur Rahman Khan and Frei Otto.
- It is assumed that you know which of these names are historically connected with 19th-century colonial architecture in India.

Concept / Approach:
Frederick William Stevens was a British architectural engineer who worked in Bombay (now Mumbai) during the late 19th century. He designed the Victoria Terminus building for the Great Indian Peninsula Railway, blending Gothic Revival with Indian elements. Santiago Calatrava is a contemporary Spanish architect known for modern, sculptural bridges and buildings. Fazlur Rahman Khan was a 20th-century structural engineer associated with skyscrapers in the USA, and Frei Otto was a German architect known for tensile structures. None of these latter three were involved in designing CST.

Step-by-Step Solution:
Step 1: Recognize that Victoria Terminus was completed in the late 19th century under British colonial rule. Step 2: Identify Frederick William Stevens as the British architect who designed this railway headquarters and station in Bombay. Step 3: Note that Santiago Calatrava, Fazlur Rahman Khan and Frei Otto belong to a much later, 20th-century context and are not linked to Victorian-era buildings in India. Step 4: Therefore, Frederick William Stevens is the correct answer.

Verification / Alternative check:
A quick verification can be made by recalling that CST is often cited in heritage literature as Stevens' most famous work in India, showcasing a blend of Gothic Revival architecture with domes, turrets and Indian motifs. In contrast, Calatrava is associated with works like the Turning Torso and various bridges; Fazlur Khan is known for structural systems like the framed tube in skyscrapers; and Frei Otto is linked to lightweight tensile structures such as the Munich Olympic Stadium roofs.

Why Other Options Are Wrong:
Option B, Santiago Calatrava, is a modern architect whose career post-dates the construction of CST by about a century. Option C, Fazlur Rahman Khan, revolutionized skyscraper design but had no role in colonial Indian railway architecture. Option D, Frei Otto, focused on experimental, lightweight roof structures and did not work on Victorian Gothic buildings in India. Thus, none of these names aligns with the historical and stylistic context of CST's design.

Common Pitfalls:
Candidates sometimes ignore time periods and choose names based purely on familiarity, even if the architect worked in a different century. Others may confuse CST with modern transport structures and associate it with contemporary architects like Calatrava. Always check whether the architect's career fits the era and style of the building in question.

Final Answer:
The Chhatrapati Shivaji Terminus railway station in Mumbai was designed by the British architect Frederick William Stevens.