What does almost all energy on Earth come from?

Most of the energy comes from Sun. It is the main source of energy which helps in completing photosynthesis, provides natural light to the entire earth

Using Sun, electricity can be produced using solar cells

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.

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