<span>More often than not, it would be the northwestern regions of Thailand that are not marketed very often and do not show up in the brochures. These would include the regions of the Mae Sot province, Kampheng Phaet and Sukhothai. This is mostly because this area is surrounded by a mountainous region which makes it quite inaccessible to most tourists. Because of this, most people prefer to visit the more crowded and accessible areas of Thailand such as Bangkok.
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I'm 90% sure it's a "noun clause"
The Answer Would Be "All of the choices are correct"
The metric system has a lot of smaller more precise measurements than us in the US.