The play begins __ half past seven. BblGepuTe oluH OTBeT. a. to b.on c. at

The correct answer is c. at.<br /><br />In this context, the preposition "at" is used to indicate a specific time. The sentence "The play begins at half past seven" means that the play starts at 7:30. The preposition "at" is commonly used to specify precise times.