The correct answer is: C. GSM and IS-136
HSCSD (High Speed Circuit Switched Data) is a 2G mobile data technology that allows for faster data transfer speeds than the original GSM (Global System for Mobile Communications) standard. It does this by using multiple time slots to carry data, rather than just one. This means that HSCSD can achieve data rates of up to 57.6 kbps, which is significantly faster than the 9.6 kbps data rate of standard GSM.
HSCSD is supported by both GSM and IS-136, which are two of the most common 2G mobile standards. It is not supported by PDC (Personal Digital Cellular), which is a 2G mobile standard that is used in Japan.
Here is a brief explanation of each option:
- A. GSM: GSM is a 2G mobile standard that was developed in Europe in the early 1980s. It is the most widely used 2G mobile standard in the world, and it is used in over 200 countries. GSM uses digital technology to provide voice and data services.
- B. IS-136: IS-136 is a 2G mobile standard that was developed in the United States in the early 1990s. It is the second most widely used 2G mobile standard in the world, and it is used in over 100 countries. IS-136 uses digital technology to provide voice and data services.
- C. GSM and IS-136: HSCSD is supported by both GSM and IS-136. It does this by using multiple time slots to carry data, rather than just one. This means that HSCSD can achieve data rates of up to 57.6 kbps, which is significantly faster than the 9.6 kbps data rate of standard GSM.
- D. PDC: PDC is a 2G mobile standard that is used in Japan. It is not supported by HSCSD.