Hesitating what to do,          .

A．so let’s not go outing

B．we had to stay home

C．the tour was cancelled

D．but we should still take the tour

根据《本地通信线路工程设计规范》，埋式电缆的埋深，一般情况下应大于或等于（）。埋式电缆上方应加覆盖物保护，并设标志。