Depth or height of the arch is the A. Perpendicular distance between intrados and extrados B. Vertical distance between springing line and intrados C. Perpendicular distance between springing line and extrados D. None of the above

The correct answer is: A. Perpendicular distance between intrados and extrados

The intrados is the inner curve of an arch, while the extrados is the outer curve. The depth or height of an arch is the perpendicular distance between these two curves.

The springing line is the line where the arch meets the vertical supports. The vertical distance between the springing line and the intrados is called the rise of the arch. The vertical distance between the springing line and the extrados is called the span of the arch.

The depth or height of an arch is an important factor in determining its strength. A deeper arch is stronger than a shallower arch. This is because the weight of the arch is distributed over a larger area, which makes it less likely to collapse.

The depth or height of an arch is also an important factor in determining its appearance. A deeper arch is more dramatic than a shallower arch. This is because the curves of a deeper arch are more pronounced.

In conclusion, the depth or height of an arch is the perpendicular distance between the intrados and extrados. It is an important factor in determining the strength and appearance of an arch.