The police have arrested a 17-year-old boy accused of writing a blasphemous remark in an examination paper, an officer said Tuesday. Pakistan’s blasphemy laws have come under scrutiny since the killing last month of a prominent politician who had campaigned to change them. They allow for the death penalty for anyone found guilty of insulting Islam. The school authorities lodged a complaint against the boy, identified as Sami Ullah, in January after reading a paper he wrote for an exam in Karachi, said the officer, Qudrat Shah Lodhi. Officer Lodhi said he could not repeat what Sami, who is a Muslim, had written because he would be committing blasphemy. He said the boy told the police that he had written the remark out of frustration when he was not able to answer the exam question. The boy was arrested Saturday.