Line 1: *Some parasites live on the surface of their host. Leeches are external parasites. Leeches are on the surface of the host .*
*(B)*
Line 2: *What unwanted creature would be found on the surface of a human body using it as a host?
Options:
- (A) Tapeworm.
- (B) Leeches.
- (C) Pesticides
- (D) animals
- (E) insects
- (F) Hookworm
- (G) bacteria
- (H) Bracelet.*

Logic of a solution: *Air pollution harms the respiratory and circulatory systems. Incinerated mercury pollutes the air. Incinerated mercury harms the respiratory and circulatory systems.*
*(D)*
The original question: *What harms the respiratory and circulatory systems?
Options:
- (A) Greenhouse gasses
- (B) burning coal
- (C) inoculation
- (D) incinerated mercury
- (E) fossil fuels
- (F) water vapor
- (G) Sulfur dioxide
- (H) air*

Line 1: *Balance is the ability to sense and maintain body position. Another part of the inner ear is used for balance. The inner ear helps with sensing and maintaining body position.*
*(C)*
Line 2: *This helps with sensing and maintaining body position:
Options:
- (A) lightheaded
- (B) sweating
- (C) inner ear
- (D) cochlea
- (E) four limbs
- (F) nerves
- (G) Riding a bike
- (H) dizzy*

Logic of a solution: *Wings are part of the exoskeleton and attached to the thorax. Spiracles are located on the abdomen and thorax. Wings and spiracles share a location.*
*(A)*
The original question: *What shares a location with spiracles?
Options:
- (A) wings
- (B) pistons
- (C) white
- (D) bats
- (E) animals
- (F) insects
- (G) pollen
- (H) ovaries*

Line 1: *Mollusks reproduce sexually. An abalone is a shellfish or mollusk. Abalone reproduce sexually.*
*(F)*
Line 2: *Abalone is an example of an animal that:
Options:
- (A) refract or absorb.
- (B) They have webbed feet
- (C) important habitats
- (D) Plant growth is reduced
- (E) it keeps an organism warm
- (F) reproduces sexually
- (G) decreases its bodily water
- (H) four limbs*

Line 1: *Reproduction is the process by which living things give rise to offspring. Most people want to have children who are the biological offspring of both parents. Reproduction is the process by which living things produce children.*
*(H)*
Line 2:
*What comes from reproduction?
Options:
- (A) babies
- (B) protein
- (C) pollution
- (D) dead cells
- (E) Energy
- (F) seeds
- (G) Most plants
- (H) children*