阅读下面短文，从短文后的选项中选出可以填入空白处的最佳选项。选项中有两项为多余选项。
When buying a backpack, there are several things you should consider. {#blank#}1{#/blank#}A backpack used for carrying school supplies, for example, may not need to have as many features as a backpack that is to be used for hiking or camping.
When buying a backpack，look for one that can easily be placed on your back. Many people carry their backpacks over only one shoulder.{#blank#}2{#/blank#}Backpacks are designed to be carried completely on your back, supported by both shoulders, in order to help evenly distribute (分配) the weight. In fact, carrying a backpack that is either too heavy or used improperly is one of the leading causes of back injuries in students.
{#blank#}3{#/blank#} If the backpack will be used for carrying textbooks, it must be wide enough to contain the width of the books it will carry. If the backpack is for hiking, it needs to be large enough to carry supplies such as a solar blanket and other camping things.
Another consideration when buying a backpack is the number of compartments (隔层) the backpack has. When used for hiking or camping, it's often helpful for a backpack to have several smaller compartments. {#blank#}4{#/blank#}
The material is also important when buying a backpack. When buying a backpack for hiking or camping, it is best to buy one that is strong enough. {#blank#}5{#/blank#} If you are buying a backpack for college use, it might also help prevent your books and homework from getting wet while you are walking from one building on campus to another in the rain.
A. But this is actually a mistake.
B. There are backpacks different from traditional ones.
C. It is helpful to buy a backpack with much space inside.
D. It is important to buy one that will be comfortable to carry.
E. This way, important items such as knives are easy to reach.
F. Thus, your clothing or supplies will not get damaged in bad weather.
G. The most important consideration when buying a backpack is its future use.
