ANS:C - Both (a) & (b).

Both options (a) and (b) are examples of stress corrosion.

• Season cracking of brass is a type of stress corrosion that occurs in brass due to the combined action of stress and a specific corrosive environment, typically ammonia or ammonia compounds. This type of corrosion can lead to the formation of intergranular cracks in brass components.
• Caustic embrittlement of steel is another form of stress corrosion that occurs in steel exposed to caustic environments, such as concentrated alkaline solutions. In this process, the steel becomes brittle and susceptible to fracture under stress in the presence of caustic substances.