单项选择题
A technician installs a new sound card but no sound can be heard. Which of the following utilities can be used to see an error?（）
A. MSCONFIG B. Device Manager C. DXDIAG D. REGEDIT
单项选择题 Which of the following 802.11 standards can operate at both 2.4 GHz and 5.0 GHz?（）
单项选择题 Which of the following is the correct pin out for T568B?（）
单项选择题 Which of the following is a multimedia device?（）
