Not All Amino Acids Have to Be Supplied by Food

Not all amino acids have to be supplied by food. This is true because:

A) not all necessary amino acids are found in food.
B) hormones furnish the missing amino acids.
C) the body is able to manufacture some amino acids from others.
D) the liver is able to manufacture some amino acids from fatty acids.
E) the human body does not require all amino acids.