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

Which of the following definitions best describes 'histone H2AK13 ubiquitin ligase activity'?

A. Catalysis of the transfer of a ubiquitin molecule to histone 2A at the lysine-127 residue.
B. Catalysis of the transfer of a ubiquitin molecule to histone 2A at the lysine-129 residue.
C. Catalysis of the transfer of a ubiquitin molecule to histone 2A at the lysine-15 residue.
D. Catalysis of the transfer of a ubiquitin molecule to histone 2A at the lysine-13 residue.

Answer: Catalysis of the transfer of a ubiquitin molecule to histone 2A at the lysine-13 residue.