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The color of the flowers on the hydrangea bush was blue last year, and now it is pink. The only change was a recent addition of lime to the soil surrounding the hydrangea bush.

Which of the following occurred within the hydrangea plant to cause it to produce a different color of flower?


There was a mutation in the gene that controls the color of the flowers. This mutation resulted in the change of the color of the flower on the hydrangea.


There was an increase in available water this year to the hydrangea plant which diluted the color of the flower from blue to pink.


The types of hormones produced by the hydrangea plant changed. This hormonal change caused the color of the flower to change from blue to pink.


The gene that codes for the color of the flowers can be affected by the pH of the soil. The change in pH changed the phenotype of the flower.