Sleuth can offer a bit of protection (3)

I believe the answer is:

tec

I'm a little stuck... Click here to teach me more about this clue!

'sleuth' is the definition.
(short for detective)

'offer a bit of protection' is the wordplay.
'TEC' is hidden in amongst the letters.
However, I'm unsure how this is indicated.

'can' acts as a link.

Can you help me to learn more?

(Other definitions for tec that I've seen before include "CID officer (abbrev.)" , "Busy" , "Detective (colloq.)" , "Investigator" .)

I've seen this clue in the Evening Standard.

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