The correct options are
A Deforestation
B Loss of biological diversity
Criticism to the construction of large dams causes environmental problems as they require vast area. A huge number of trees need to cut down from this area which further results in soil erosion and loss of biological diversity. Building large dams can cause serious geological damage. For example, building the Hoover Dam in the USA triggered a number of earthquakes and has depressed the earth's surface at its location. Huge financial investment and maintenance are also problems of dams but are not related to the environment.