Fill the blank with the correct option:

Yard is to inch as quart is to____.

Fill the blank with the correct option:

Secretly is to openly as silently is to ____.

Fill the blank with the correct option:

Reptile is to lizard as flower is to ____.

Fill the blank in the middle of the series or end of the series:

SCD, TEF, UGH, ____, WKL.

Fill the blank in the middle of the series or end of the series:

JAK, KBL, LCM, MDN, ____.

Which one set of letters when sequentially placed at the gaps in the given letter series will complete it?

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