In the first paragraph, the word "discarded" means
a) lost
b) thrown away
c) uninteresting
d) insignificant
" the phrase "garbage patch" brings to mind an image of a colossal island of trash overflowing with discarded tires, styrofoam food containers, detergent bottles, aluminum cans, and mounds upon mounds of empty plastic bottles."

B

Explanation:

Discarded is used to refer to something that has been thrown away or placed in the garbage due to disuse. Items like tires eventually wear out and are often sent to dumps before being recycled. The word discarded is strongly associated with refuse and unwanted items.

In much the same way, ideas can also be discarded as not worth the effort or resources to carry out.