Answer:
we need to know the definitions of the two types of mutations:
- A chromosomal mutation is a change in the structure or number of chromosomes, which are the structures that carry genes. Examples of chromosomal mutations are deletions, duplications, inversions, and translocations.
- A gene mutation is a change in the sequence of nucleotides, which are the building blocks of DNA and RNA. Examples of gene mutations are substitutions, insertions, and deletions.
Looking at the definitions, we can see that a chromosomal mutation can affect many genes at once, while a gene mutation can affect only one or a few nucleotides. Therefore, a chromosomal mutation could have the most drastic effect on a gene, because it could alter or delete an entire gene or multiple genes, resulting in major changes in the phenotype or function of an organism. A gene mutation could also have significant effects on a gene, but it could also be silent or minor depending on the location and type of the mutation. Therefore, the answer is a chromosomal mutation. One possible way to back up this choice is to give an example of a chromosomal mutation that causes a genetic disorder, such as Down syndrome or Turner syndrome.