मानक भवन नियमों के अनुसार, आवासीय भवनों के लिए बिना नोजिंग (without nosing) के ट्रेड (tread) की न्यूनतम चौड़ाई कितनी होनी चाहिए?

Read the given statements of Assertion (A) and Reason (R) carefully and select the correct option. Assertion (A): Expansion joints in concrete structures are continuous, unobstructed slots filled with compressible materials such as bitumen-impregnated fiberboard, cork, cellular rubber, or polyethylene foam to permit thermal or moisture expansion. Reason (R): The compressible filler absorbs expansion and contraction movements, preventing stress build-up and avoiding cracks or spalling in adjoining concrete parts.

In India, which of the following timbers is most commonly used for scaffolding?