Line 1: *Biodiversity increases the productivity and stability of ecosystems. Islands are delicately balanced ecosystems. Biodiversity increases the stability and productivity of islands.*
*(B)*
Line 2: *Biodiversity increases the what of islands?
Options:
- (A) water source
- (B) stability
- (C) Plants growth
- (D) our planet
- (E) luminescence
- (F) environment
- (G) human population
- (H) allow growth*

Logic of a solution: *Migration is a type of movement that changes population size. Predatory animals migrate with the game animals. As movement causes a change in game population size, predatory population size changes, too.*
*(C)*
The original question: *When game animals move elsewhere, what else does?
Options:
- (A) relocation
- (B) prey animals
- (C) predatory animals
- (D) migratory birds
- (E) An object is seen
- (F) migrants
- (G) refract or absorb.
- (H) barks and snarls*

Line 1: *Most mollusks have shells. Mussels are bivalve mollusks. Mussels have shells.*
*(D)*
Line 2: *Mussels have what?
Options:
- (A) seaweed
- (B) arms
- (C) Energy
- (D) a shell
- (E) warmth
- (F) bacteria
- (G) Length
- (H) legs*

Logic of a solution: *Viruses cannot reproduce by themselves. Viruses include the Tobacco Mosaic Virus. The Tobacco Mosaic Virus cannot reproduce by itself.*
*(B)*
The original question: *The tobacco mosaic virus cannot _ by itself.
Options:
- (A) migrate
- (B) reproduce
- (C) move
- (D) consume
- (E) It expands
- (F) animals
- (G) survive
- (H) respirate*

Line 1: *Ethologists usually study how animals behave in their natural environment. Environments are animals homes. Ethologists usually study how animals behave in the animals' homes.*
*(G)*
Line 2: *Ethologists study how animals behave in animals'
Options:
- (A) Summer
- (B) state
- (C) Birds
- (D) life
- (E) seasons
- (F) health
- (G) homes
- (H) fields*

Line 1: *Migration is a type of movement that changes population size. Predatory animals migrate with the game animals. As movement causes a change in game population size, predatory population size changes, too.*
*(C)*
Line 2:
*When game animals move elsewhere, what else does?
Options:
- (A) relocation
- (B) prey animals
- (C) predatory animals
- (D) migratory birds
- (E) An object is seen
- (F) migrants
- (G) refract or absorb.
- (H) barks and snarls*