Explanation:

- Option 1: Helium

- When electricity flows through helium, it emits a pale lavender or pinkish light.

- Not typically associated with producing a red glow.

- Option 2: Argon

- Argon emits a violet or pale lavender-blue light.

- Commonly used in fluorescent lighting and signs, but not for red light.

- Option 3: Nitrogen

- Emits a blue or purplish light.

- Often used in some types of lasers but not known for red light emission.

- Option 4: Neon

- Neon produces a bright red-orange light when electricity is passed through it.

- Widely used in advertising signs for its distinctive warm glow.

Your Answer: Option 4 - Neon