Correct answer: (b) Wireless communication technology
Explanation
- A
Waste management technology
Waste management. Project Loon is not a landfill or waste-to-energy project. This letter is not the key.
- B
Wireless communication technology
Wireless communication. Alphabet/Google’s Project Loon used high-altitude balloons to beam internet connectivity to the ground—a wireless last-mile idea. That stored letter is the official key.
- C
Solar power production technology
Solar power production. Balloons may carry solar panels for their own power, but the project’s purpose is connectivity, not utility-scale solar. This letter is not the key.
- D
Water conservation technology
Water conservation. Loon is unrelated to watersheds or irrigation. This letter is not the key.
Summary. Official key is (b) wireless communication technology. Project Loon floated stratospheric balloons to deliver internet. It is not waste, solar-farm or water tech. Honour the stored letter (b).