根据短文内容，从短文后的七个选项中选出正确的填入空白处。选项中有两项为多余选项。
The Science of Risk-Seeking
Sometimes We decide that a little unnecessary danger is worth it because when we weigh the risk and the reward, the risk seems worth tasking. 71 Some of us enjoy activities that would surprise and scare the rest of us. Why? Experts say it may have to do with how our brains work.
The reason why any of us take any risks at all might have to do with early humans. Risk-takers were better at hunting, fighting, or exploring. 72 As the quality of Risk-taking was passed from on ration to the next, humans ended up with a sense of adventure and a tolerance for risk.
So why aren’t we all jumping out of airplanes then? Well, even 200,000 years ago, too much risk-taking could get one Killed. A few daring survived, though, along with a few stay-in-the-cave types. As a result, humans developed a range of character types that still exists today. So maybe you love car racing, or maybe you hate it. 73
No matter where you are on the risk-seeking range, scientists say that your Willingness to take risks increases during your teenage years. 74 To help you do that, your brain increases your hunger for new experiences. New experiences often mean taking some risks, so your brain raises your tolerance for risk as well.
Mean taking some risks, so your brain raisers your tolerance for risk as well.
75 For the risk-seekers a part of the brain related to pleasure becomes active, while for the rest of us, a part of the brain related to fear becomes active.
As experts continue to study the science of risk-seeking, we’ll continue to hit the mountains, the waves or the shallow end of the pool.
73（）
A．It all depends on your character.
B．Those are the risks you should jump to take.
C．Being better at those things meant a greater chance of survival.
D．Thus, these well-equipped people survived because they were the fittest.
E．This is when you start to move away from your family and into the bigger world.
F．However, we are not all using the same reference standard to weigh risks and rewards.
G．New brain research suggests our brains work differently when we face a nervous situation.
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