Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'imidazopyrimidopyrimidine'?

A. An epoxide resulting from the oxidation of the double bond at the 2-3 position of aurachin C.
B. Any organic heteropolycyclic compound that is derived from a cladoniamide.
C. An organic heterotricyclic compound that is imidazole which is ortho fused to a pyrimidine ring which itself is ortho fused to a pyrimidine ring.
D. Any organic heterotricyclic compound whose core skeleton consists of a benzodioxin ring that is ortho-fused to a pyran ring.

Answer: An organic heterotricyclic compound that is imidazole which is ortho fused to a pyrimidine ring which itself is ortho fused to a pyrimidine ring.