She has many an alternative choice (6)
I believe the answer is:
mother
'she' is the definition.
Both the definition and answer are singular nouns.
Perhaps you can see an association between them that I don't see?
'many an alternative choice' is the wordplay.
I cannot really see how this works, but
'many' could be 'm' and 'm' is found within the answer.
'alternative' could be 'other' (I've seen this before) and 'other' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'has' acts as a link.
Can you help me to learn more?
(Other definitions for mother that I've seen before include "Be overprotective" , "Nature so-called" , "Female parent" , "- - 7 across, pantomime" , "Parent to her Tom, oddly" .)