Most of the guests arrived . . . . . . . . buses. A. in B. from C. by D. with

The correct answer is C. by.

The preposition “by” is used to indicate the means of transportation. In this case, the guests arrived by buses.

The other options are not correct because:

• A. in is used to indicate a location or position. In this case, the guests did not arrive in buses, they arrived by buses.
• B. from is used to indicate a starting point or origin. In this case, the guests did not arrive from buses, they arrived by buses.
• D. with is used to indicate accompaniment or possession. In this case, the guests did not arrive with buses, they arrived by buses.