下列哪些是M600的特点（）。

• A、成本低
• B、透明性，传输业务种类多；(Transparent and various types of transmission service)
• C、简单，集成度高；(Simple and highly integrated)
• D、具有保护；(With the protection function)
• E、没有保护；(Without the protection function)
• F、最高速率可达10G (The highest rate can reach 10G)