Answer:
the tigris and Euphrates river flow through Syria and Iraq into the Persian Gulf.
Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds.
Water pollution affects the entire biosphere – plants and organisms living in these bodies of water. In almost all cases the effect is damaging not only to individual species and population, but also to the natural biological communities.
The massive rain forest is one of the major barriers to travel in the Congo region. The correct option among all the options that are given in the question is option "c". This rain forest is very dense in some places and it is almost impossible to pass through it. I hope the answer helps you.