Why does Bihar produce so many IAS, IPS or IIT, IIM grads?

Bihar is a state difficult to understand. On one side, 80% of the population is uneducated. There are hardly any studies throughout the year due to politics, frequent strikes and absenteeism. Many parents have to sell off their property to send their sons or daughters to Delhi, Mumbai, Bangalore or any other such metro cities for education. Still the state manages to produce the highest numbers of IAS, IPS & IFS officers. Almost 25 percent of the 700 IAS and IPS officers in the last ten years are Biharis.