Which of the following may be associated with the collision of two sections of continental crust

Of the following choices;

The answer is; earthquakes and a mountain range

When the two continental plates collide, there is enormous stress between the two plates and this is why such boundaries are hot spots for earthquakes. When the two plates collide, the submerged plate (usually the oceanic plate) uplifts the continental plate and causes it to fold into a mountain range called fold mountains (an example is the Alps and Andes Mountain Range).  

answer; ///i believe that the correct answer is (the worksheet);

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.