What are three possible ways that a mutation could change dna, yet have no measurable effect on the organism?

Some mutations don't have any noticeable effect on the phenotype of an organism. This can happen in many situations: perhaps the mutation occurs in a stretch of DNA with no function, or perhaps the mutation occurs in a protein-coding region, but ends up not affecting the amino acid sequence of the protein.

Cbecause it is the only one describing a habitat