Answer:
Actually question says which of the following where as there is no option given.
It is basically effect of environment on expression of gene for colour.
Explanation
pH of soil could be tested where hydrangea is being grown using pH meter. Colour of plant could be noted by growing at that particular pH keeping all other conditions as constant. It has blue colour in acidic soil and pink colour in alkaline soil.
When light passes from a material of one refractive index to another (for example: from glass to air), it bends.
I think it would be that anatomically gorillas are more like humans.<span />
