Correct

断线

/ duànxiàn /
Strokes

Definition

(of a guitar, kite etc) to have a string break/(of a tradition etc) to be discontinued/(telephone or Internet connection) disconnected/cut off

Example

As a Verb

disconnect; break off

1
Diànhuà
电话
duànxiàn
断线
le

The (telephone) line has gone dead. / The line is dead.