Which UNIX command correctly changes the case of only the first three lines of the file "shortlist" from lower case to upper case?

1. A(A) $ tr '[a-z]' '[A-Z]' shortlist | head -3
2. B(B) $ head -3 shortlist | tr '[a-z]' '[A-Z]'
3. C(C) $ tr head -3 shortlist '[A-Z]' '[a-z]'
4. D(D) $ tr shortlist head -3 '[a-z]' '[A-Z]'

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