Q. Change the speech:
The Technician told us how to maintain the machine in good working order.

• (A) The technician said to us, “This is how you maintained the machine in good working order.”
• (B) The technician said to us, "That is how you maintained the machine in good working order.”
• (C) The technician said, “This is how you maintain the machine in good working order.”
• (D) The technician said to us, “There is how you maintained the machine in good working order.”