The correct option is
D Half past nine
Kodus and Klang wake up at half past seven in the morning.
At half past seven, the hour hand is between 7 and 8, and the minute hand points at 6.
After waking up, they take one hour to get ready.
The time by which they are ready is one hour from half past seven.
So, if we add one hour to half past seven, we will get half past eight.
At half past eight, the hour hand is between 8 and 9, and the minute hand points at 6.
After getting ready, they take one hour to have breakfast before starting the class.
So their breakfast time for one hour starts from half past eight.
So the breakfast time will end at half past nine after which they start the class.
At half past nine, the hour hand is between 9 and 10, and the minute hand will point to 6.
So, we can conclude that they start the class by half past nine.