instruction:
Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.
question:
Fact: DNA strands are called a polynucleotide. 
Question: What is a DNA strand?
answer:
Polynucleotide.


question:
Fact: if graptolites are found in a place then that place used to be covered by water. 
Question: what are found in place to indicate a place used to be covered by water?
answer:
graptolites.


question:
Fact: The most ancient seed plants are trees with woody trunks. 
Question: The most ancient what are trees with woody trunks?
answer:

seed plants.