以下background-position属性的取值方式正确的是A.background-position:topcenter;B.background-position:10%20%;C.background-position:30px;D.background-position:30px100px;

In css style, the meaning of background-position:-10px 20px is ( ) A: The background<br/>picture is offset by 10px to the left and 20px to the down B: The background<br/>picture is offset by 10px to the left and 20px to the top C: The background<br/>picture is offset by 10px to the right and 20px to the down D: The background<br/>picture is offset by 10px to the right and 20px to the upper

In css, the background picture needs to be located in the lower left corner of the box and should be written as: ( ) A: background-image:left foot B: background-image:left bottom C: background-position:left foot D: background-position:left bottom

{在CSS中属性background-position: right;还可以写成其他等价属性值，以下哪个是不正确的？（ ）。} A: background-position: 50% 100%; B: background-position: 100%; C: background-position: 100% 50%; D: background-position: right center;

在CSS中，background复合属性可以设置下列哪些属性的值。 A: background-color B: background-image C: background-repeat D: background-position E: background-size