Question

Fill in the blank with a suitable preposition:
How can you send a message faster than _______ letter?

• A. At
• B. Within
• C. On
• D. By

Answer 1

The correct option is D By

The given sentence indicates means of communication.

We can determine the correct answer with the help of logic and by eliminating the incorrect answer.

'At', 'within' and 'on' are used to indicate position. They do not fit in the given sentence. We can thus eliminate options A,B,C as incorrect answers.

By is used to indicate means of communication. Hence option D is the correct answer.