Choose your weapon? (4,3)

I believe the answer is:

pick axe

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'weapon?' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'choose your' is the wordplay.
'choose' becomes 'pick' (picking is a kind of choosing).
'your' becomes 'axe' (I can't explain this - if you can you should believe this answer much more).
'pick'+'axe'='PICK AXE'

Can you help me to learn more?

I've seen this clue in The Sun.

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