Question: Which of the athletes with initial O that was known for doping and came from the most populous country in Africa was born the earliest ?

text: List of doping cases in athletics
O

The use of performance-enhancing drugs (doping) is prohibited within the sport of athletics. Athletes who are found to have used such banned substances, whether through a positive drugs test, the biological passport system, an investigation or public admission, may receive a competition ban for a length of time which reflects the severity of the infraction. Athletes who are found to have banned substances in their possession, or who tamper with or refuse to submit to drug testing can also receive bans from the sport. Competitive bans may also be given to athletes who test positive for prohibited recreational drugs or stimulants with little performance-enhancing effect for competitors in athletics. The sports body responsible for determining which substances are banned in athletics is the World Anti-Doping Agency (WADA). Typically, any athlete who tests positive for banned substances after having served a previous ban receives a lifetime ban from the sport of athletics. Many high-profile sportspeople to receive doping bans have come from the sport of athletics, with significant past cases concerning Ben Johnson, Lance Armstrong, Alberto Contador, Shane Warne, Diego Maradona, Shoaib Akhtar, Marion Jones and Tim Montgomery. Furthermore, a number of athletes who underwent state-sponsored doping programmes in East Germany between the 1960s and 1980s were competitors in athletics, but the quality of the international anti-doping work was so poor that only one East German athlete ever tested positive. Following allegations of state-sponsored doping in Russia, the IAAF suspended the country's athletes from competition, including the 2016 Summer Olympics.
Name Country Event Date of violation Banned substance ( s ) / Anti-doping rule violation Sanction
Musa Amer Obaid Qatar Steeplechase 2006 Testosterone 2 years
Al Oerter United States Discus throw 1976 Anabolic steroids . ( Self-admitted ) -
Deborah Oluwaseun Odeyemi Niger Sprinting 2015 Metenolone 4 years
Amaka Ogoegbunam Nigeria Sprinting 2009 Metenolone 3 years
Femi Ogunode Qatar Sprinting 2011 Clenbuterol 2 years
Christine Ohuruogu Great Britain Sprinting 2006 3 whereabouts failures 1 year
Aham Okeke Norway Sprinting 1994 2006 Testosterone , Pseudoephedrine Testosterone 30 months Life ban
Samuel Okon Nigeria Hurdling 2010 Methylhexanamine
Iulia Olteanu Romania Cross country 1996 Stanozolol 2 years
Omolara Omotosho Nigeria Sprinting 2009 Metenolone 2 years
Mary Onyali-Omagbemi Nigeria Sprinting 1996 Ephedrine 3 months
Janet Ongera Kenya Long distance 2002 Norandrosterone 2 years
Josephine Onyia Spain Hurdling 2008 2011 2015 Methylhexaneamine , Clenbuterol Methylhexaneamine Metenolone 2 years 2 years Life ban
Charity Opara Nigeria Sprinting 1992  4 years
Helder Ornelas Portugal Marathon 2010 Biological passport 4 years
Yolanda Osana Dominican Republic Hurdling 2012 Stanozolol 2 years
Oludamola Osayomi Nigeria Sprinting 2010 Methylhexaneamine
Artur Osman Poland Long distance 2005 Norandrosterone 2 years
Nadzeya Ostapchuk Belarus Shot put 2012 2005 ( Retested in 2012 ) Metenolone Formestane , 4-Hydroxytestosterone 4 years
Hanane Ouhaddou Morocco Steeplechase 2009 Biological passport 2 years