To prepare for the slippery slide down, riders put on a soft helmet and some arm pads. Then they lie on a mat. The mat has a pocket for their feet and a strap to hold as they slide. Workers can't secure, or attach, the mat to the rider so riders must hold that strap tightly all the way down. What does "secure" mean in this passage?

A. to feel safe.

B. to hold lightly.

C. to slide down.

D. to fastern firmly.​

D. to fasten firmly.

Explanation:

The answer is in the passage "...or attach..."

To attach also means to fasten firmly.

i believe that dan is so anxious because he dose not know what awaits him when he gets there. but i dont know to be honest

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