Which of the following supports the claim that the environment can affect genetic traits? A Oak trees get taller as they grow. B Hydrangea flower color varies with soil pH. C Dandelion plants are self pollinating. D Pinion trees bear cones every other year.

The answer is B Hydrangea flower color varies with soil pH.

If environmental factors are variable in an area, they can affect some genetic traits. Soil pH is one of the environmental factors. If Hydrangea flower color depends on this environmental factor, then it can affect genetic traits.

The other choices cannot be right because they do not contain any environmental factor - growing, self-pollinating and cone bearing are definitely not environmental factors.