Answer: B im pretty sure.
The correct answer is B. pollution.
Humans evolved 3 billion years ago after the earth was formed.<span />
Answer:
Sharks, in their basal form have been on Earth for hundreds of millions of years. They were the first to develop a stream-like, torpedo shaped body and created a niche for themselves. Their aerodynamic body shape has evolved to allow for efficient and dynamic movement in water. Having a cartilage instead of bones allowed them to grow large and still be relatively light and buoyant . After they've evolved flexible, protruding jaws, there wasn't much to change. They were able to adapt and exploit all the water habitats as the world was changing.
Explanation:
Answer: Chemical bonds
Explanation: an atom has a positively charged nucleus surrounded by a cloud of electrons.