451. Which among the following is responsible for producing color of human skin ___?
A. Insulin
B. Vitamin K
C. Melanin

452. Which one of the following can be synthesized by Liver _______?
A. Vitamin B6
B. Vitamin B12
C. Vitamin K
D. Vitamin E

453. What is/are the basic purpose(s) of dams?
A. Storage of water in a large reservoir
B. Generation of electricity
C. Control of floods
D. All of the above

454. The point that lies directly above the source of an earthquake is known as _______________ ?
A. Earthquake Center
B. Epicenter
C. Gravitational Center
D. Geological Center

455. Which one is the world’s largest mangrove forest(s)?
A. Changa Manga Forest
B. Amazon Forest
C. Sundarbans Forest
D. None of the above

456. The rocks formed out of layers of sediment bonded together are known as _______________?
A. Metamorphic rocks
B. Sedimentary rocks
C. Igneous rocks
D. All of the above

457. What is the name of the central part of the earth?
A. Mantle
B. Core
C. Crust
D. None of the above

458. Evaporation from ice and snow is known as___________?
A. evaporation
B. sublimation
C. hydrogenation
D. insolation

459. Ice mass that covers more than fifty-thousand square kilometers of land area is classified as____________?
A. ice sheet
B. ice field
C. glacier erosions
D. ice cap

460. Pedosphere is sum of_____________?
A. Organisms
B. Soil and water
C. Air
D. All of above