q: What is just one of many ways that pugs learn how to behave.
Options:
- (A) humans
- (B) playing
- (C) sleeping
- (D) growing
- (E) Movement
- (F) sound
- (G) genetics
- (H) exercise
a: (B)... Explanation: Playing is just one of many ways that mammals and other animals learn how to behave. Pugs are mammals and mammals shed. Playing is just one of many ways that pugs learn how to behave. That's why the answer is (B).

q: What do many plants do to respond to the shorter days in fall?
Options:
- (A) go through a resting period
- (B) changing the phase
- (C) Release energy
- (D) Generating heat
- (E) produce more pollen
- (F) colder and wetter
- (G) grow taller
- (H) make more chlorophyll
a: (A)... Explanation: Many plants respond to the days growing shorter in the fall by going dormant. Plants can be divided at any time, although the dormant or rest period is best. Many plants respond to the days growing shorter in the fall by going through a rest period. That's why the answer is (A).

q: How can cells of the tobacco mosaic be seen?
Options:
- (A) refraction of light
- (B) an area swollen with pus
- (C) by indirect light
- (D) death and devastation
- (E) bending light rays
- (F) electron microscope
- (G) deadly and devastating
- (H) Veins and arteries.
a: (F)... Explanation: Viruses are so small that they can be seen only with an electron microscope. Viruses include the Tobacco Mosaic Virus. Tobacco Mosaic is so small that it can only be seen with an electron microscope. That's why the answer is (F).

q: When insects move from one place to another, this usually causes
Options:
- (A) seed dispersal
- (B) Transfers energy
- (C) change in mood
- (D) death and devastation
- (E) change in population size
- (F) change in individual insect
- (G) change in shape
- (H) converting mass to energy
a:
(E)... Explanation: Migration is a type of movement that changes population size. Insects can also migrate. Insects sometimes change population size by moving from one place to another. That's why the answer is (E).