There are a few ways to remove drop shadow in Illustrator. The first way is to use the Shadow tool. To use the Shadow tool, click on the shadow object and then click on the Shadow button. The Shadow tool will create a drop shadow over the object. The second way is to use the Stroke tool. To use the Stroke tool, click on one of the shadows and then drag it to another shadow object. The two shadows will have different Stroke values. The third way is to use the Mask tool. To use the Mask tool, click on one of the shadows and then select its mask thumbnail. Then, click on another shadow and select its mask thumbnail to make it an overlay mask for that shadow object.