Question

AM is used for broadcasting because (A) it is more noise immune than other modulation system (B) it requires less transmitting power compared with other system (C) it avoids receiver complexity (D) No other modulation system can provide the necessary band width faithful transmission

Short answer

The correct answer is (C) "it avoids receiver complexity." AM is used for broadcasting because it results in simpler and more affordable receivers compared to other modulation systems.

Step-by-step solution

Analyzing choice (A)

Let's analyze option (A): "it is more noise immune than other modulation systems." In reality, AM is not more noise immune compared to modern modulation systems such as Frequency Modulation (FM) and digital modulation schemes. In fact, AM is more susceptible to noise than these other systems. So, this option is incorrect.

Analyzing choice (B)

Now let's analyze option (B): "it requires less transmitting power compared with other systems." Option (B) is true, as AM does require less transmitting power compared to other systems like FM or digital modulation systems. However, this reason alone is not sufficient to justify the use of AM in broadcasting, as other factors need to be considered.

Analyzing choice (C)

Next, let's analyze option (C): "it avoids receiver complexity." This statement is true. AM receivers are relatively simple and inexpensive compared to other modulation systems. This is one of the main reasons why AM is used in broadcasting, especially in areas where receiver cost is a significant factor.

Analyzing choice (D)

Finally, let's analyze option (D): "No other modulation system can provide the necessary bandwidth faithful transmission." This statement is false. Modern digital modulation systems can provide high-fidelity transmissions with limited bandwidth. So, this option is incorrect.

Conclusion

Based on the analysis of each option, the correct answer is (C) "it avoids receiver complexity." This is because AM receivers are simpler and more affordable compared to those needed for other modulation systems.