The leaning tower of Pisa does not fall because:

Detailed Solution:

The correct answer is “the vertical line through the centre of gravity of the tower falls within the base”.

For any object to remain stable and not fall over, its center of gravity must be aligned vertically over its base of support. In the case of the Leaning Tower of Pisa, even though it leans, its center of gravity is still positioned over the area of its base, allowing it to remain standing.