The correct answer is: a) Increasing internet access.
The internet has become increasingly accessible in Sikkim in recent years, with more and more people having access to high-speed internet. This has led to a growing demand for online news, and many newspapers have responded by launching online editions. This allows them to reach a wider audience, both within Sikkim and beyond.
The other options are not as likely explanations for the growth of online newspapers in Sikkim. Government regulations are unlikely to be a major factor, as there are no specific regulations governing the online publication of newspapers in Sikkim. Environmental concerns about paper use may be a concern for some people, but it is unlikely to be a major factor in the decision of newspapers to launch online editions. A desire to reach a wider audience is a more likely explanation, but it is not as likely as increasing internet access.
In conclusion, the correct answer is: a) Increasing internet access.