If a base-pair change occurs during dna replication, this

is a mutation.
would be a mutation only if it falls in a protein-coding part of a gene.
would be a mutation only if it falls in a transcribed part of the genome.
is not a mutation, because only one base pair has been altered.

Correct "is a mutation"

This is the best answer choice because a mutation when at least one base pair changes to another.

Incorrect Answers:

"would be a mutation only if it falls in a protein-coding part of a gene"

Some mutations are more influential than others. If this mutation occurred in a region that codes for a protein, then it could greatly influence the structure/function of the the protein and therefore the cellular processes that the protein is used for. Oppositely, mutations can occur in regions that don't code directly for a protein and therefore could go completely unnoticed, making this a bad answer choice.

"would be a mutation only if it falls in a transcribed part of the genome."

A mutation can occur when the gene in transcribed from DNA → RNA, but the process of transcription is separate from that of DNA replication so that makes this answer choice not so good.

"is not a mutation, because only one base pair has been altered."

A mutation can be just when one base pair is altered, so this is an incorrect statement.

the growth of the plants is affected by the heat of the light. what is the student doing?

because photosynthesis could not occur (apex)