Many people believe that the common garden slug[  is nothing more than a pest that should be wiped out. In attempts to beautify their yards, people employ various poisons, strategically chosen plants, and gardening techniques. Success is attained when no trace of slugs can be found, although the worn-out gardener still watches and waits for their return, as completely ridding a garden of slugs is almost impossible.    Experts, however, have discovered that the slug's evil reputation as an enemy of home gardeners may, in fact, be groundless to some degree. Although it is true that a slug can devour[  garden plants from the roots up in amazing quantities, it also produces nutrients for the soil, which help other plants grow. The diet of a slug consists of plant waste and mould, as well as living plants, making it a sort of natural recycling center. The unique structure of a slug digestive system enables it to take these discarded  products, transform them into the nutrients that plants need, and then release those nutrients harmlessly as wastes.    To some, this situation is unacceptable. No gardener wants to sacrifice his or her plants just to gain a few nutrients that could easily be provided by fertilizers In order to achieve a balance, both slug and gardener may have to compromise some things. One  ly easy step is to separate plants with high slug appeal from those with low appeal. That way, the sections of the garden spared for plants with high slug appeal can contain plants that the gardener is willing to sacrifice so as to protect those plants that have a lower slug appeal . Another possibility is to leave some ground-covering plants in a less tidy state, since slugs particularly enjoy semi-decayed  plant matter. The slugs will then be drawn toward this decaying matter instead of toward the living plants.          These measures may seem slow and difficult but they are still preferable to commercial slug repellents   for several reasons. The topsoil of a garden is often highly lacking in nutrients, due to chemical damage caused by just such products. The fertilizer industry sells millions of pounds of dirt mixed with the nutrients necessary for a healthy garden every year. Yet these are the very same minerals that a healthy slug population would provide at no cost. Moreover, since slugs find newly dead slugs highly appetizing. the slug population is unlikely to decrease significantly as a result of these severe measures. According to the passage, the wise way to deal with slug problem is that we should   _  ,
apply as many kinds of commercial repellents as possible to the plant roots sacrifice some plants and keep semi-decayed plant matter as food for slugs employ all possible gardening techniques to get rid of slugs completely protect the garden from slugs by keeping it in a clean and tidy state