Read the given passage and answer the questions that follow.

In the span of just two decades, the number of mobile telephone subscriptions exploded from essentially zero to 6.9 billion. The mobile revolution originated in the rich world, and by the year 2000, high-income OECD countries already boasted 50 subscriptions per 100 population. In low-income countries, however, the rate was still less than 1 subscription per 100 population. Thanks to fast-paced growth, the developing world started to bridge this “mobile divide.” Whereas high-income countries still boasted 18 times more subscriptions per 100 population than low-income countries in 2005, this ratio had dropped to 2 times by 2013.
Arguably, the mobile revolution’s influence has been greatest in the developing world, where it has helped address the critical lack of telecommunication infrastructure and improve access and productivity in sectors such as agriculture, health, education, and finance. While this is truly remarkable, one must acknowledge the limits of this mobile revolution.
First, even though there are almost as many mobile telephone subscriptions as people on the planet, this does not imply that everyone owns or is using a mobile phone. The number of mobile subscriptions far exceeds the number of mobile phone users. Based on the GSM Association’s estimates that unique mobile subscribers account for about half of mobile cellular subscriptions. ITU reckons that mobile telephony penetration has reached approximately 48 percent globally and 30 percent in least-developed countries.
Second, even in countries where penetration rates exceed 50 percent, vast disparities exist between urban and rural areas. Indeed, parts of the developing world are not yet covered by a mobile network signal. ITU calculates that, at the end of 2012, around 450 million people worldwide still lived out of reach of a mobile signal.
Third, only so much can be done through 2G mobile telephony, which can carry only voice and text messages. The most compelling and promising solutions for development require more sophisticated technologies: first and foremost is fast and reliable access to the Internet, be it mobile, wireless, or wired access. But the Internet is neither as ubiquitous nor is it spreading as fast as many believe. Beyond mobile telephony, the digital divide still runs deep. There is a stubbornly high correlation between income and performance in the ICT usage pillar. In this category, the score gap between high-income economies and the rest of the world is large and has actually been widening since 2012: lower-middle-income and low-income countries are now farther behind than they were in 2012. The relationship between income and ICT impacts is almost as strong, providing an illustration of the new digital divide as we termed it in 2013.