Fill in the blank with the correct option.
When did you last hear _____ Don? He phoned me just this morning, He's coming to Delhi next week, so we agreed ______ a time and place to meet.
A preposition is a word which comes before a noun or a pronoun and establishes a relationship between the elements of a clause or words. Option A)from;on is correct as from and on indicate a source and involvement. The other options are wrong as about, at, and of indicate a piece of information, a specific location, and possession respectively. These uses don't fit in the given question. The correct answer is A)from;on.