Task: Question Answering
Input (English): Question: It is not included among the lipids found in biological membranes: 
 Options:  <1> Isopentenyl pyrophosphate. <2> Phosphatidylinositol. <3> Sphingomyelin <4> Phosphatidic acid. <5> Phosphatidylethanolamine.
Output (English): 1