Which of the following structures is widely known in architecture as the world's tallest twisted tower, noted for its striking helical design?

Introduction / Context:
In modern architecture, some skyscrapers are designed with a noticeable twist or helical shape. Among these, one tower became especially famous and was widely reported as the tallest twisted tower in the world at the time of its completion. This question checks if the learner can identify that specific building from a list of famous structures.

Given Data / Assumptions:

• The question refers to the world tallest twisted tower.

• It emphasises the tower striking helical design.

• Options list several well known tall structures and towers.

• The learner is expected to recall which one is particularly known for its twist.

Concept / Approach:
Infinity Tower, also known as Cayan Tower in Dubai, is noted for its twisted architectural form, rotating around its axis as it rises. While Burj Khalifa is currently the tallest building in the world, it is not twisted in the same way. The approach is to distinguish between structures known for height alone and those known for a twisting design, then match the latter category with Infinity Tower.

Step-by-Step Solution:
Step 1: Focus on the phrase tallest twisted tower and notice that the key feature is twisting rather than overall height alone. Step 2: Recall that Infinity Tower or Cayan Tower in Dubai is famous for its helical, rotating design. Step 3: Consider the other options: Tokyo Sky Tree is a tall broadcasting tower but not primarily twisted, BREN Tower is an older structure, and Burj Khalifa is a straight super tall skyscraper. Step 4: The Leaning Tower of Pisa leans but is not twisted; it is also far shorter than modern skyscrapers. Step 5: Conclude that Infinity Tower is the structure that fits the description and select it.

Verification / Alternative check:
Architectural references, news reports and tourism materials related to Dubai describe Infinity Tower as a skyscraper with a ninety degree twist over its full height. Many sources label it as one of the tallest twisted towers in the world. While rankings can change as new buildings are constructed, exam questions generally reflect the widely accepted status of Infinity Tower at the time the question was framed, which supports this answer.

Why Other Options Are Wrong:
Tokyo Sky Tree is a broadcasting and observation tower in Japan; it is tall but does not have a pronounced helical twist. BREN Tower is not widely known for a twisted design and is not commonly featured in such questions. Burj Khalifa holds the title of tallest building in the world but its form is not categorised as a twisted tower. The Leaning Tower of Pisa is famous for its lean rather than a twist and is also of modest height compared to modern skyscrapers. Therefore, these structures do not match the specific description in the question.

Common Pitfalls:
Some learners may impulsively choose Burj Khalifa whenever they see the word tallest, without reading the word twisted carefully. Others may be distracted by the world wide fame of the Leaning Tower of Pisa and think that leaning and twisting are the same concept. To avoid such errors, it is important to pay attention to the exact wording and to recognise that architectural records can be specific to particular design features, not just overall height.

Final Answer:
The structure widely known as the world tallest twisted tower is Infinity Tower.