Analyze the relationship between 'Boko Haram' and 'Abubakar Shekau' within the context of the input sentence.
Options: director/manager, publisher, product/material produced, chairperson

Boko Haram has released a new video on the insurgency in Nigeria, with its leader Abubakar Shekau again failing to … see more » Copyright © 2015 Daily Trust.
chairperson