资料：As more personal business is conducted through smartphone devices , more users are implementing security measures for their devices, according to a recent survey by Harris Poll and commissioned by the CTIA.

The survey was a part of the company’s ongoing efforts to boost user education on the pitfalls of mobile security and assess whether the CTIA’s initiatives are working.

It turns out that mobile users in the US have begun implementing many of the initiatives set forth and have increased both awareness of, and protection for, their mobile devices:

More smartphone users are protecting their devices with PINs and passwords than in previous years. In 2016, of smartphone users had some sort of PIN/password, up from 2015 and form 2012.

An increasing number of smartphone users have installed built-in remote lock-and-erase software. Of survey respondents, have this type of lock-and-erase software installed, up an astounding from 2015 and from 2012.

Smartphone users are increasingly aware of the importance of anti-virus software. of smartphone users have an anti-virus software installed, compared with only of smartphone owners in 2015, according to BI Intelligence.

The survey results indicate that users are becoming increasingly aware of the danger posed by the increasing reliance on mobile technology form not only malicious entities like hackers, but also government surveillance. Specifically, users are increasingly seeking for ways to guard themselves in light of a number of recent high-profile incidents involving phone security–like Apple's case against the FBI, for example.

Because of this, it will become increasingly common for app developers and device manufactures to build in security and end-to-end encryption. This can be seen in devices and apps such as WhatsApp and iPhones. Developers and device manufacturers that don't include this feature in their products could be faced with negative consumer attitudes.

According to the passage, _____ of smartphone users had some sort of PIN/password in 2015 and 2012.

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• D.and