Problem: OPTIONS:
- population age
- the environment
- population education
- general preferences
- important habitats
- population size
- movement
- an organism's body
Q: Fact 1: Migration is a type of movement that changes population size. Fact 2: Birds migrate to escape poor weather and food supply. Given the two facts above, escaping poor weather and food supply changes what?
Answer: population size

Problem:OPTIONS:
- disease
- pollen counts
- advanced mathematics
- microorganisms
- migrating birds
- viruses
- Physical weathering
- harmful substances

Fact 1: Microorganisms can cause infections. Fact 2: Leeches clean away the dead or infected tissue. Given the two facts above, dead tissue can be caused by what?
****
A: microorganisms

Fact 1: Vertebrates are animals that have a backbone. Fact 2: Trunk muscles are the muscles of abdominal wall, thorax, backbone and pelvic cavity. Given the two facts above, vertebrates are animals that have what?
OPTIONS:
- strength
- tentacles
- Something to move
- tree muscles
- animal suits
- trunk muscles
- Epidermis
- aerobic capacity
trunk muscles

Fact 1: Most mollusks have shells. Fact 2: Mollusks are the second-largest invertebrate group. Given the two facts above, what do the second-largest invertebrate group have?
OPTIONS:
- shells
- a cuticle
- insects
- barnacles
- animals
- tortoises
- alveoli
- honeybees

Answer: shells

Question: Fact 1: Changes in the pH of soil can cause plants to die. Fact 2: Sulfur lowers pH in soil. Given the two facts above, adding sulfur to soil can cause what?
OPTIONS:
- contamination
- flooding
- plants to die
- Pollution
- chemical reaction
- Greenhouse gasses
- global warming
- harmful substances
Answer: plants to die

input: OPTIONS:
- sperm
- parent
- DNA
- ancestor
- child
- gametes
- haploid
- self Now, answer this question: Fact 1: Amutation in the sex cells of a parent can cause a new trait to appear in the parent 's offspring. Fact 2: Child' is ambiguous between 'offspring' and 'immature offspring'. Given the two facts above, a mutation in the sex cells of a parent can cause a new trait to appear in the parent 's what?
A:
output:
child