What is the study of fossils called?

Convergent evolution is illustrated by

Which of the following are homologous organs?

Which of the following examples show divergent evolution?

Sweet potato shows analogy with .........

In evolution,studies can be conducted at the molecular level. For example,proteins found in the blood of humans and apes are similar. The base sequences in nucleic acids and amino acid sequences in proteins are similar in related organisms. What do all these examples specifically refer to?