Which of the following is the best marker for drug induced lupus?

Drug induced lupus is associated with anti histone antibodies which are positive in 95% of cases. Ref: Harrison's Principles of Internal Medicine, 17th Edition, Page 2076; 16th/ 1961, 1967; Pathologic Basis of Disease, Robbins, 7th Edition, Page 229 & 235; Drug-Induced Diseases: Prevention, Detection, and Management, James E. Tisdale, 2nd Edition, Section 2, Page 108