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suppose I have 2 associations

t1=<|"a" -> 1, "b" -> 2, "c" -> 3, "d" -> 4|>

and

t2=<|"a" -> x, "a1" -> x^2, "b0" -> x^3, "b" -> x^4, "b1" -> x^5, 
 "c" -> x^6, "c1" -> x^7, "c2" -> x^8, "d" -> x^9|>

How can I from t2 select those elements that are in t1? The output would look like:

<|"a" -> x, "b" -> x^4,"c" -> x^6, "d" -> x^9|>

I tried pick as Pick[t2,t1] yet it returns an empty sequence.

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KeyIntersection[{t1, t2}][[2]]

<|"a" -> x, "b" -> x^4, "c" -> x^6, "d" -> x^9|>

or

KeyTake[t2, Keys[t1]]

<|"a" -> x, "b" -> x^4, "c" -> x^6, "d" -> x^9|>

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Query[Keys[t1]]@t2

<|"a" -> x, "b" -> x^4, "c" -> x^6, "d" -> x^9|>

t2[[Keys @ t1]]

<|"a" -> x, "b" -> x^4, "c" -> x^6, "d" -> x^9|>

KeySelect[t2, AssociationThread[Keys[t1] -> True]] (* or *)
KeySelect[t2, MemberQ[Keys[t1], #] &]

<|"a" -> x, "b" -> x^4, "c" -> x^6, "d" -> x^9|>

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