Laura's selective about who may introduce them (8,7)

I believe the answer is:

relative clauses

'who may introduce them' is the definition.
(a relative clause could begin with 'who')

'laura's selective about' is the wordplay.
'about' is an anagram indicator.
'lauras'+'selective'='laurasselective'
'laurasselective' anagrammed gives 'RELATIVE CLAUSES'.

I've seen this clue in The Guardian.

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