Sarah Montague speaks to Nigeria's aviation minister Osita Chidoka. Nigeria's 2015 presidential election has been described as the most important in decades. Whoever wins will have to take on the militant Islamist group Boko Haram and deal with an economy hit hard by the falling oil price. The choice for voters is between President Goodluck Jonathan and the former military dictator Muhammadu Buhari, with the polls suggesting they are neck and neck. President Jonathan has said he is 'hopeful' that those parts of Nigeria under Boko Haram will be taken back before the election. But how can his government defeat Boko Haram in a matter of weeks when it has failed to do so in six years in government?