Why did demand for railway sleepers put more pressure on particular trees?

Correct answer: Because sleepers needed strong and durable timber

The direct answer is option A: railway sleepers needed strong and durable timber, so particular suitable trees were cut more heavily. A sleeper is a piece of wood or another material placed under railway rails to support and keep them correctly spaced. Railways required very large numbers of sleepers, and they had to withstand weight, weather, and long use. Therefore officials and contractors preferred species whose wood was hard and durable, creating concentrated pressure on those trees rather than equal pressure on every species. Option A is correct. B is wrong because a tree does not become a sleeper automatically; it must be selected, felled, and processed. C is wrong because railways were not made only of grass. D is wrong because durable wood had great practical value. Exam cue: railway expansion plus durable timber means selective pressure on strong tree species.