HSK C4/W3/V7-9
Correct

独

/ dú / 
Strokes

Definition

alone/independent/single/sole/only

Example

As an Adjective
only; single; sole; lone; solitary
As a Noun
old people without offspring; the childless
As an Adverb
alone; on one's own; by oneself; in solitude
As an Adverb
only; no one except
As an Adverb
uniquely
As an Adjective
intolerant