阅读下面短文，从短文后各题的A，B，C，D四个选项中，选出适合填入对应空白处的最佳选项。
When I was 16, I wrote a list of things I wanted to do in my lifetime. Some things were easy, some difficult and some almost 1. One of the things on the list was to do a 2.
Two years ago I spent three months travelling with a friend and it was a great experience. One of the most 3 things we saw was Iguassu Falls. The day after we visited the waterfalls we were 4 in a hotel in Brazil, playing games when my friend 5 noticed an advertisement on the wall 6 “Skydive over Iguassu Falls today!”. I realized it was time to realize my 7. Today would be the day that we would jump out of a(n) 8.
That afternoon we were 9 and taken to the Skydive Centre. We put on our harnesses（跳伞装备）and helmets, were given some 10 and then took off into the air. My heart started to beat very fast and I felt very 11.
Luckily, I was 12 to an instructor so I didn't have to worry about anything; I just had to 13 myself. He asked me if I was ready to fall from the plane but 14 I had enough time to 15, we fell to the ground at 400 km an hour! After about 40 seconds of 16, the parachute opened and everything slowed down. We 17 peacefully towards the earth, leaving the 18 behind us.
This was definitely one of the scariest but most exciting 19 of my life. I would do another skydive if I had the20. I think that everyone should do something that scares them once in a while！
p或q”是真命题，而“p且q”是假命题，则a的取值范围是