当其他一切条件相同，设某建筑物抗震设防烈度为7度时所受的总水平地震作用为F，8度时所受的总水平地震作用为F，则F与F存在下列何种关系?

• A.F<img src="https://timg.fentiku.com/101/2016/10/21/XgZPmg7VNa.png" title='XgZPmg7VNa.png' alt='XgZPmg7VNa.png'/>=1．125F<img src="https://timg.fentiku.com/101/2016/10/21/Ua9PuaSiif.png" title='Ua9PuaSiif.png' alt='Ua9PuaSiif.png'/>
• B.F<img src="https://timg.fentiku.com/101/2016/10/21/zchiFq067S.png" title='zchiFq067S.png' alt='zchiFq067S.png'/>=2F<img src="https://timg.fentiku.com/101/2016/10/21/mDT0gVyVnM.png" title='mDT0gVyVnM.png' alt='mDT0gVyVnM.png'/>
• C.F<img src="https://timg.fentiku.com/101/2016/10/21/6FX8qWxnJW.png" title='6FX8qWxnJW.png' alt='6FX8qWxnJW.png'/>=1．5F<img src="https://timg.fentiku.com/101/2016/10/21/6g53jFpMop.png" title='6g53jFpMop.png' alt='6g53jFpMop.png'/>
• D.F<img src="https://timg.fentiku.com/101/2016/10/21/7x7us8Bht7.png" title='7x7us8Bht7.png' alt='7x7us8Bht7.png'/>=1．25F<img src="https://timg.fentiku.com/101/2016/10/21/XKFWrbdzH6.png" title='XKFWrbdzH6.png' alt='XKFWrbdzH6.png'/>

正确答案：B