听力原文：M Okay, your vehicle is ready to go. We changed the oil and examined your brakes.

The brakes look fine. W Really？ That surprises me. They've been squealing so much, especially in the city. And every time I'm on the freeway, if I put on the brakes the car seems to rattle, really shake around a lot in the back.

M Well, I drove the car around the block and applied the brakes several times, and I didn't hear a single squeal. As for the rattling, have you considered there might be something in your trunk that's causing the rattle？

W Oh no, I didn't even think about that. Now that you mention it, I have parts of a bed frame. back there. I'll take it out and see if the car continues to shake. But that still doesn't explain the squealing.

What does the man say he did？

A．Put a bed frame. in the trunk

B．Changed the oil

C．Ordered a new part

D．Inspected the motor