It could harm birds that fly into it, it can take up space and disturb an animals habitat, and i cant think of another but i tried :)
The correct answer is - C.) eliminating barriers to trade benefits the economies of member nations.
The regional trade blocs, in fact all trade blocks, are very useful for the economies of the countries that are members in the trade block. The benefit can be seen in the economic sector, as the countries can both, export products on larger markets without tariffs, and import products without imposing tariffs, which benefits the consumers as the prices are lower in that way.
The trade blocks have become a common thing in the world during the 20th century, and that has helped the economies of lot of countries, as well as the choices available and buying power of the consumers.
The given question is incomplete as the options are missing. The options related to the given question are as follows-
(A) Crust is formed
(B) Mountains are formed
(C) Seafloor spreading occurs
(D) Crust becomes molten rock
(E) Denser plates slide under lighter plates
Answer:
Options (C), (D) and (E)
Explanation:
Trenches are usually defined as the V-shaped depressions that are formed in the convergent plate boundary, where the denser plate sinks below the lighter one.
These are usually extended up to a great depth, such as the the Mariana trench which is about 11 km deep. These trenches marks the boundary between the two plates.
In a convergent plate boundary, with a distinct deep oceanic trenches, the seafloor spreading takes places extensively, and the downgoing crust undergoes partial melting and becomes hot molten rocks that eventually mixes up with the magma.
Thus, the correct answers are options (C), (D) and (E).