Select the most appropriate option to fill in blank number 1.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3, i.e. greenhouse.
The sentence says:
“The burning of fossil fuels releases greenhouse gases, such as carbon dioxide, into the atmosphere, leading to the (1) _____ effect.”
This refers to the well-known scientific phenomenon—the greenhouse effect, where greenhouse gases trap heat in the atmosphere and warm Earth’s surface. This matches perfectly here. Scientific sources describe how fossil fuel combustion increases greenhouse gas concentrations and strengthens the greenhouse effect, amplifying global warming and altering climate patterns.
Why the other options don’t work
Visual effect – No meaningful idiom or scientific term fits this context.
Sound effect – Totally unrelated to climate processes or atmospheric science.
Red sea effect – Makes no sense in English idiom or science; likely incorrect and irrelevant here.