Read the following context and choose the best option to answer the question.
Context: Every year more than 400 billion cups of coffee are sold , meaning that billions of plastic and cardboard cups are being thrown into the environment . I realised that taking your own mug to a cafe or coffee chain is one of the simplest things to do , yet nobody does it . For those who buy one , two or even three coffees a day , they could personally save between 365 - 1095 cups a year just by taking their own with them when they get a coffee .
Question: Why is it a matter of concern that so many disposable cups are used ?
Options: 
A. There is only so much plastic to go around
B. None of the above choices .
C. People really do not like disposable cups
D. They are damaging the environment


D