Fill in the blank with the correct option:
She did not agree _______ your proposal.
a. within
b. in
c. to
d. none of these

Hint: Prepositions are the function words that combine a noun phrase or used to show a relationship between words in a sentence. For example, she was sitting under a tree. Here, under is a preposition that is being used to connect the verb, ‘sitting’ with the noun phrase, ‘a tree’.

Complete answer:
From the hint given to us, we understand the meaning of a preposition. Let us analyse the given options one by one to find the correct answer.
Within means inside something. For example, there were not many literate people within her community. We observe that it does not correctly fit the context of the given sentence. Hence, we can say that option ‘a’ is not the correct answer.
In means enclosed or surrounded by something. For example, she lives in a bungalow. We observe that it does not correctly fit the context of the given sentence. Hence, we can say that option ‘b’ is not the correct answer.
To is used for indicating agreement or accordance. For example, she agreed to meet you. We observe that it correctly fits the context of the given sentence. Hence, we can say that option ‘c’ is the correct answer.
None of these is an invalid option as option ‘c’ is the correct answer.
Thus, we can conclude that option ‘c’ - ‘to’ is the correct answer.

Note: It is to be noted that the meanings of the prepositions vary with respect to the context they are used in. Hence, one must be familiar with prepositions to answer such questions correctly.