Correct

单传

/ dānchuán /
Strokes

Definition

to have only one heir in a generation (of a family, clan etc)/to be learned from only one master (of a skill, art etc)

Example

As a Verb

have only one son for several generations in a row

As a Noun

patrilineal succession of descents with only one son in each generation

As a Verb

pass on a skill from one master to a single learner