Question 16

The passage suggests that the light bulbs used in the first train signaling systems were all the same color.

The early train signaling systems utilized light bulbs that produced red and green signals through the use of colored filters. This indicates that the bulbs themselves emitted a uniform white light, with color differentiation achieved solely through the filters.

A) They were very fragile.

The passage does not provide any information regarding the fragility of the light bulbs used in the early signaling systems. Therefore, this option is incorrect as it introduces an assumption not supported by the text.

B) They were all the same color.

This option is correct because the passage explains that the bulbs produced a clear white light, and colors were generated by filters. Consequently, regardless of the color displayed, the bulbs themselves were uniform in color.

C) They were only illuminated at night.

The passage does not suggest that the bulbs were only used at night. In fact, train signals were likely utilized throughout the day as well, making this statement inaccurate.

D) They were also used to signal automobile drivers.

The passage focuses solely on train signaling systems and does not mention any connection to automobile drivers. Therefore, this option is incorrect as it misrepresents the context provided.

Conclusion

Option B is definitively correct because it aligns with the information presented in the passage regarding the uniformity of the light bulbs used in early train signaling systems. In contrast, the other options either introduce unsupported claims or misinterpret the context, failing to accurately reflect the details discussed in the passage.