50. ___
A. Protect roads along the shore.
Build on beaches with seawalls.
C. Add sand to beaches with seawalls.
D. Stop building seawalls.
40. ___
A. Problems with pesticides.
B. Characteristics of one type of falcon.
C. Migratory patterns of birds.
D. Tracking systems for animals.
43. ___
A. How animals react to frightening situations.
B. Why mice are particularly fearful animals.
C. Whether fearfulness is a genetic trait.
D. Why certain animals are feared by humans.
44. ___
A. They fought with the other mice.
B. They stayed close to their mothers.
C. They ran back and forth constantly.
D. They remained close to one wall.
45. ___
A. The extent of damage to the nervous system.
B. The presence or absence of certain nerve-cell receptors.
C. The size of nerve-cell receptors in the brain.
D. The level of danger in the mammal’s environment.
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