A delivery boy started from his office at 10 a.m. to deliver an article. He rode his scooter at a speed of 32 km / h. He delivered the article and waited for 15 minutes to get the payment. After the payment was made, he reached his office at 11.25 a.m., travelling at a speed of 24 km / h. Find the total distance travelled by the boy.

• A. 35 km
• B. 40 km
• C. 32 km
• D. 30 km