Chirping, if that's what you mean.
Answer:
Circulatory system
Explanation:
It can carry energy and oxygen to cell as well as waste out of cell example carbondioxide
Answer:
Genetic variations that alter gene activity or protein function can introduce different traits in an organism. If a trait is advantageous and helps the individual survive and reproduce, the genetic variation is more likely to be passed to the next generation (a process known as natural selection)
Answer is C .. Hopes this help a lot ;)
