You are given an elementary science question along with a few answer options. List all the words from the question that are essential and sufficient for choosing the correct answer option. Keep in mind that essential words are necessary to understand the meaning of the given question. However, non-essential words provide little information needed to select the correct answer. You can think about it like this: If the question was in another language, knowing the meaning of which words were necessary and enough for you to understand the question and answer it?. If your answer consists of multiple spans of words from the question, separate those using a comma (", "). Do not generate any word that is not present in the question. Make sure that your response is contained in the given question and the words are in the same order as the question.
 Grammatical correctness is not important.

Question: Which of these organisms has cells with cell walls? (A) bluebird (B) A pine tree (C) A ladybug (D) A fox squirrel?
organisms, cells, cell, walls?

Question: Which two observations are both used to describe weather? (A) precipitation and runoff (B) temperature and sky conditions (C) wind speed and erosion (D) types of clouds and deposition?
observations, describe, weather?

Question: How do the petals of a flower help with reproduction? (A) They absorb energy from the Sun and produce food for their offspring. (B) They protect the plant from insects during seed production. (C) They make the flower attractive to bees and butterflies. (D) They are where plants incubate their offspring.?

petals, flower, help, reproduction?