With reference to street-lighting, how do sodium lamps differ from LED lamps? 1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps. 2. As street-lights, sodium lamps have longer life span than LED lamps. 3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street-lighting. Select the correct answer using the code given below.

Statements 1 and 3 are correct because sodium lamps emit light omnidirectionally (360°) and produce a monochromatic yellow light, whereas LEDs are directional and offer a broad color spectrum for better visibility. Statement 2 is incorrect because LEDs have a significantly longer lifespan (up to 50,000+ hours) compared to high-pressure sodium lamps (around 24,000 hours). The core concept tested is the comparative physical and functional properties of traditional versus modern lighting technologies.