The correct answer is: B. 2.25 m.
Ballast is a layer of crushed stone or other material that is used to support the railway track. It provides a stable foundation for the track and helps to distribute the weight of the train evenly. The width of the ballast section is important to ensure that the track is properly supported and that there is enough space for the train to pass safely.
Option A is incorrect because it is the width of the ballast section for Meter Gauge. Option C is incorrect because it is the width of the ballast section for Narrow Gauge. Option D is incorrect because it is the width of the ballast section for Standard Gauge.
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