In the context of the input sentence, determine the relationship between 'Boko Haram' and 'Abubakar Shekau'.
Options: headquarters location, chairperson, location of formation, creator

Leader of the Boko Haram sect, Abubakar Shekau has again resurfaced in a recording and denied claims by Chadian … see more » Copyright © 2015 Premium Times.
chairperson