In this question, a pair of words is given with certain relationship followed by four pairs of words. Choose the pair that best expresses a relationship similar to that expressed in the original pair.
MAN : HUMANITY

The initial pair, "MAN : HUMANITY," illustrates a part-to-whole connection, where "MAN" represents an individual within the broader collective of "HUMANITY." Thus, the appropriate answer choice should reflect a similar part-to-whole relationship. 

Let's analyze the options.

Option-A: Drop : Ocean:

A drop is a tiny component of a much larger expanse of water, like an ocean. This aligns correctly with the initial pair.

Option-B: Flower : Fragrance:

Although related, this does not exemplify a part-to-whole relationship. A flower generates a fragrance, yet the fragrance is not a component of the flower itself.

Option-C: Frame : Picture:

A frame surrounds and holds a picture, showcasing a container-to-contents relationship rather than a part-to-whole relationship.

Option-D: Scholar : Books:

A scholar is an individual who studies and engages with books, but a book is not a component of the scholar.

So, correct answer is option-A.