It is D .......................
According to the excerpt, the option that identifies an implicit meaning one could draw from it would be the second one: "Locke is unfamiliar with the term <em>idea</em>".
In the excerpt, Locke is not asking what Idea is nor is he being uncertain about the relationship between speculative and practical ideas. He seems to never heard it before and the exact meaning fades away.
That's why he asks what it represents and not its definition or for someone to repeat the explanation. He just needs an example to clarify the boundaries of the <em>idea's</em> meaning.
Dear mom ,
How are you wish you are fine there I want to write the letter from so many days but didn't getting the time I want to say that the festival of Diwali is coming all my friends hv the set of new clothes I don't hv please buy me the new clothes on this diwali please buy a set of jeans and a shirt hope u will buy..I love u mom and father..bye
Your son
a noun
jack and milly came to tea
jack is he,milly she and little susie? well that's me