How could an error during transcription affect the protein that is produced?

An error during transcription could produce a shorter protein or induce changes in the protein's sequence.

Explanation: Transcription is the process of single-stranded RNA synthesis from a DNA template (gene). During this process, RNA polymerase reads the DNA template and synthetize RNA, keeping the sequence. The RNA sequence will be reading later by ribosomes and protein will be produced. An error in transcription could produce changes in codons that are sequences of 3 nucleotides that determine  aminoacids of the protein, and that would change protein folding and inactive it. Another possible result would be that  error in transcription produce a premature stop codon that cause a shorter inactive protein.

they have identical fossils of organisms that have evolved over time.

both have animal fossils preserved in them due to weathering and erosion.

they contain different fossils because life on earth has changed through time.

the fossils in them were formed on the surface of earth due to exposure to sunlight.