The answer is letter A.
Dogs grow a thick coat fur during winter because they are adapting to change. Adaptations are
the result of evolution in different living organisms. This process occurs amazingly
through gene mutation but it takes a very long period in time. Adaptation
processes occur to help species survive and thrive in the ecological balance of
life.
Structural adaptations are physical features of an organism that adapted
through time. An example of this is the thick coat of fur that dogs naturally grow to protect themselves from the change of the weather.
Lignin
It is a complex organic polymer that form an important structural materials in the support system of vascular plants and can also be found in some algae. This is an important molecule in the structural composition of cell wall, such as in wood and bark. This also allow woods and barks to have strong, rigid which allows them to no break easily. Lignin can also be found inserted in the cell wall of this plants.
Fracking sites release a toxic stew of air pollution that includes chemicals that can cause deserve headaches, asthma symptoms, childhood leukemia, cardiac problems, and birth defects(it can also cause cancer). Fracking increases economic activity, employment, income and housing prices.
The first one i think it is the first one
