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

Which of the following definitions best describes '(9Z,12Z,15Z,18Z,21Z)-tetracosapentaenoate'?

A. A tetracosapentaenoate that is the conjugate base of (6Z,9Z,12Z,15Z,18Z)-tetracosapentaenoic acid, obtained by deprotonation of the carboxy group; major species at pH 7.3.
B. A tetracosapentaenoate that is the conjugate base of (9Z,12Z,15Z,18Z,21Z)-tetracosapentaenoic acid, obtained by deprotonation of the carboxy group; major species at pH 7.3.
C. A member of the class of cleistanthins that is the 4-O-3,4-di-O-methyl-beta-D-xylopyranoside of 1,3-dihydronaphtho[2,3-c]furan-4-ol which is substituted by an oxo group at position 1, methoxy groups at positions 6 and 7, and a 1,3-benzodioxol-5-yl group at position 9. It is one of the toxic principles in Cleistanthus collinus.
D. Any aldono-1,5-lactone having undefined stereochemistry. A representative structure is provided.

Answer: A tetracosapentaenoate that is the conjugate base of (9Z,12Z,15Z,18Z,21Z)-tetracosapentaenoic acid, obtained by deprotonation of the carboxy group; major species at pH 7.3.