Question

why do scientists study proteins to find evidence for evolution?
protein sequences never change, so scientists study proteins to discover how species of organisms evolve.
proteins reflect dna sequences, so scientists study proteins to look for genetic similarities and differences in organisms.
a lack or presence of proteins in an organisms body indicates whether the organism lives on land or in water.

Explanation:

Proteins are synthesized based on DNA sequences. By studying proteins, scientists can identify genetic similarities and differences among organisms, which is crucial evidence for evolution. Protein sequences do change over time (so the option stating they never change is incorrect). The presence or absence of proteins doesn't indicate habitat (land or water). And the key is that proteins reflect DNA sequences, allowing study of genetic aspects related to evolution.

Answer:

Proteins reflect DNA sequences, so scientists study proteins to look for genetic similarities and differences in organisms.