Why were trees like teak given more importance in commercial forestry?

Correct answer: They gave strong and useful timber

Direct answer: Option A is correct. Teak and similar trees were valued in commercial forestry because they produced strong, durable, and useful timber. The reasoning is: commercial forestry selects trees that can be sold profitably; teak wood is hard and long-lasting; it was useful for ships, railway sleepers, construction, and other works; therefore colonial forest authorities protected and planted such commercially valuable species. Option A correctly identifies strong and useful timber. Option B is wrong because trees do not produce sea salt; salt comes from saline water and evaporation. Option C is wrong because cotton is a fibre crop grown on cotton plants, not produced by teak trees. Option D is wrong because teak does not reduce land tax; taxation was a government policy, not a biological product of trees. The question is about economic usefulness, not about every function of a forest. Memory cue: commercial forestry chooses trees that give marketable timber—teak means strong wood.