"I will not choose a question based on an issue [and whether it is politics-related]," one pupil Philip Ma Chuk-ming said outside a Tin Hau exam venue.

Another candidate waiting outside Belilios Public School planned to avoid politics-related questions: "I don't know much about modern China," she said.

In one question in the three-hour exam, candidates were asked to comment on whether filibuster campaigns launched by pan-democrat legislators would harm to society.

And another included pictures of Hongkongers participating in a candlelight vigil to commemorate the Tiananmen Square tragedy and Hong Kong activists landing on the disputed Diaoyu Islands. Students were asked to explain why people in Hong Kong were motivated to do such things, and whether such events could boost people's national identity.

Examiners reiterated that markers would not judge candidates on their political views and they would earn marks if their arguments were well-established and balanced. But some pupils told internet forums they leaned towards pro-government viewpoints in the hope they would score higher marks.

One teacher, Cheung Yui-fai, said students needed to show their aptitude for critical thinking as the papers were designed to test pupils' ability to take a multifaceted approach to problems.

He thought it was a positive sign that so-called sensitive political matters were included in the exam. "It shows that the authorities did not try to avoid these, and in fact, such matters are everyday matters for students," he said.

Meanwhile, the Hong Kong Examinations and Assessment Authority confirmed yesterday that an investigation had been launched following reports of possible disruption of radio reception in the Chinese listening test held on Tuesday.

Internet reports claim a type of radio device sold by a tutoring centre could disrupt reception for other candidates. An HKEAA spokeswoman said it had to establish if the reports were true.