Organism a shares 50% of its dna sequences with organism b, while organisms b and c share 90% of their dna sequences. what can be concluded from this?

Aresearcher created three groups based on participants bmi: normal weight, overweight and obese. the hypothesis being tested is that the three groups differ in the mean number of artificially sweetened drinks consumed weekly. which statistical test might the researcher use, assuming a reasonably normal distribution of values.