In this task, you are given a sentence. You are expected to write the name of the organism substances in the body mentioned in the input. Although there might be several correct answers, you need to write one of them.

Input: Consider Input:  The glycosylation level of heparin - citrate precipitable fraction of serum which predominantly contained low density lipoprotein ( G - LDL ) also correlated well with GSP and LDL - cholesterol levels .

Output: serum


Input: Consider Input:  Our data suggest that yolk - DNA arises by the adventitious uptake of DNA present in the maternal serum by vitellogenic oocytes .

Output: serum


Input: Consider Input:  Abrupt hypertension increased blood flow to all brain regions .


Output: blood