The correct option is C
4R principle was developed for solid waste management and stands for:
Reduce - the use of non-biodegradable materials,
Reuse - materials again and again,
Recycle - use the materials that can be recycled, and
Recovery - If the waste remains after it is been reused and recycled.
Plastics are non-biodegradable and take several years to decompose. They adversely affect our ecosystem. Thus, we should avoid plastics as far as possible. Plastics can easily be recycled and reused again.
The principle 4R is also applied to all the other options but we chose plastic as our answer because it is the most polluting to our environment. Substances such as natural fibres and metals contribute much less to the damages caused by waste materials.
Option C is correct.