Question

close reading
underline the sentence
that states the central
idea.
hint
which choice restates
the central idea but does
not include opinions?
continue reading about connections in a food chain. use the close
reading and the hint to help you answer the question.
(continued from page 12)
if the snake population changes, other changes occur up and
down the food chain if the snake population increases, more
snakes eat more mice. fewer mice are left to eat acorns, so
perhaps more acorns grow into oak trees. in addition, more
snakes would mean more food for the hawks. or, consider the
alternative. if the snake population decreases, the mouse
population would increase. more mice would eat more acorns,
so fewer oak trees would grow. and the hawk population,
without snakes to hunt, might decrease as well. changing one
link in a food chain affects all of the other links, even if just in
small ways.
circle the correct answer.
which of the following best summarizes the entire scientific account?
a some people think snakes are pests, but snakes are part of the
food chain. they eat mice, which are the real pests.
b hawks are the fiercest predators in the food chain. they hunt
snakes, keeping the snake population from getting too high.
c a changing snake population would affect hawks. they would
have less to eat, so there would be fewer hawks.
d snakes play an important role in a complex food chain. their
population size affects the number of mice, hawks, and oak trees.
show your thinking
look at one of the answers that you did not choose. explain why it is not a good summary.

find an answer that includes an opinion. talk with your partner about how you identified it.

Explanation:

To determine the best summary, we analyze each option:

• Option A: Introduces opinions about snakes being pests, which the passage doesn't discuss. Eliminate.
• Option B: Focuses on hawks as the fiercest predators, but the passage is about the snake's role, not hawks' fierceness. Eliminate.
• Option C: Only addresses the effect on hawks when snakes decrease, not the full scope (including when snakes increase and effects on mice, acorns, oak trees). Incomplete. Eliminate.
• Option D: Accurately states snakes' role in the food chain and how their population affects mice, hawks, and oak trees, matching the passage's central idea.

Answer:

D. Snakes play an important role in a complex food chain. Their population size affects the number of mice, hawks, and oak trees.