A hydrangea plant has blue flowers when grown inacidic soil, but has pink flowers when grown inbasic soil. A clone of the pink-flowered plant is grown in acidic soil and produces blue flowers. This change in flower color is most likely due to:.
1) sexual reproduction in the plants, resulting in variation.
2) asexual reproduction in the plants, resulting in variation.
3) genes being expressed in different ways due to environmental conditions.
4) a gene mutation that occurred after the clone was produced.