Hey there!
Your answer: Available Space
The question is asking, which of the following options would be a (limited source). We have to find a option that has a limited source, which means that there is a limit to something. Your answer is (b) because there are limited space with the spce that is already available. Air temperature would NOT be your answer.
Answer: RNA
Explanation: I have recently learned this.
The oldest fossil evidence that geochemists have been able to find in deposits in Pilbara, Australia, and South Africa have been dated to 3.5 bya. In addition, organic compounds that may be the result of those produced by organisms have been dated, also in Greenland, to 3.8 bya.
