38 102. An applicant can only be expected to have a level of knowledge that is reasonable taking into account factors such as the applicant’s level of education and age at the time of relevant events. Nationality laws and their application can be complex. An applicant will not necessarily be able to explain clearly why a particular decision was made by authorities or what the nationality practice is in countries under consideration. Where an applicant’s ethnic identity is material to the determination, testing his or her knowledge of cultural practices or languages must take account of, inter alia, differing levels of education and understanding of traditions. Persistent unexplained evasiveness on key questions may legitimately raise concerns about an individual’s credibility on these aspects of his or her testimony. This is even more so where an individual refuses, without giving any reason, to answer certain questions. 103. When determining whether an applicant’s account is credible, a decisionmaker must evaluate whether the story presented is internally consistent. It must also be consistent with reliable information about nationality law and practice in relevant countries and whether it is corroborated by any documentary or other evidence available. Credibility is not undermined by minor inconsistencies in the applicant’s account, particularly where these are not material to the claim or relate to events that took place many years ago. Where the applicant’s testimony appears to conflict with evidence regarding the country in question, it is important to verify that there are no regional divergences or discriminatory practices on the basis of political affiliation, ethnicity, religion or other grounds in the application of the nationality mechanism in question by officials of that State. 104. An applicant’s demeanour is not a reliable indicator of credibility. A stateless person may have endured significant discrimination as a result of lack of nationality, rendering him or her anxious, reticent or defensive in any interview. Cultural differences between the applicant and the decision-maker also often preclude an accurate interpretation of specific forms of demeanour. 105. Negative inferences are not to be drawn where an individual has not had the opportunity, in an appropriate interview setting, to explain or clarify any apparent gaps, contradictions or discrepancies in his or her account. 106. The credibility of the facts material to the claim is established with reference to the credibility indicators, taking into account any reasonable explanations provided by the applicant for apparent credibility problems and with due regard to his or her individual circumstances. If, after due consideration of an applicant’s statements and all other evidence available, an element of doubt nevertheless remains in relation to the credibility of an asserted relevant fact and there is no other evidence to support that