𝗖𝗵𝗼𝗼𝘀𝗲 𝘁𝗵𝗲 𝗰𝗼𝗿𝗿𝗲𝗰𝘁 𝗼𝗽𝘁𝗶𝗼𝗻.
The Arctic is one of the last places on Earth that is still a ___________ and a _____________.
mystery, challenge
secret, mysterious
challenging, mystery