Answer:
Genetic pressure forces an animal to adapt to their environment, therefore changing their genetic code and contributing to genetic variation.
Answer:
B. Atoms are made of particles that have a negative charge.
Explanation:
Thomas is a chemist which performs an experiment using cathode ray tube. In this experiment he observed that all atoms contains electron which has negative charge. He concluded that most of mass of atom is present in the nucleus of an atom. In nucleus, proton and neutron are present which are a heavy particles and most of the space around the nucleus is empty.