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.

[EX Q]: Fact: One function of the gallbladder is to reduce the acidity of food. 
Question: What is one function of the gallbladder?
[EX A]: reduce acidity of food.

[EX Q]: Fact: Vertebrates are all chordates that have a spinal column. 
Question: What do all vertebrates have that invertebrates don't?
[EX A]: a spinal column.

[EX Q]: Fact: Antibodies are large, Y-shaped proteins designed to bind with foreign proteins. 
Question: Antibodies are large, Y-shaped proteins designed to bind with what?
[EX A]:
foreign proteins.