Answer:
c. lack the enzyme needed to break down cellulose
Explanation:
Starch is the form of carbohydrate which is taken through food by humans and animals and digested by them. Amylase is the enzyme that is used to digest starch in them.
Wood is made up of cellulose and the enzyme which is used to digest cellulose is cellulase. Humans and animals do not have cellulase enzymes therefore they are not able to digest and breakdown cellulose.
Therefore as humans and animals lack enzymes needed to digest cellulose they can not digest wood.
