A 100 V carrier is made to vary between 160 V and 40 V by the signal. What is the modulation factor?

Understanding Modulation:
Imagine a radio station broadcasting. The carrier is like the main, constant radio wave. The signal is the information (music, voice) being sent.
Modulation changes the carrier wave based on the signal. Think of it like changing the volume (amplitude modulation) of the carrier wave according to the signal's strength.

In this question:
The carrier's voltage is 100V (this is the constant part).
The signal makes the carrier voltage vary between 160V (highest) and 40V (lowest).

Calculating Modulation Factor (m):
The modulation factor shows how much the carrier's amplitude changes due to the signal. It's calculated as follows:
m = (Vmax - Vmin) / (2 * Vc)
Where:
* Vmax = Maximum voltage of the modulated carrier (160V)
* Vmin = Minimum voltage of the modulated carrier (40V)
* Vc = Voltage of the unmodulated carrier (100V)

Let's calculate:
m = (160V - 40V) / (2 * 100V) = 120V / 200V = 0.6
The modulation factor (m) is 0.6. However this value is not present in option.
Another approach to calculate modulation factor:
m = (Vmax -Vc)/Vc
m = (160-100)/100 = 0.6
or
m = (Vc-Vmin)/Vc
m = (100-40)/100 = 0.6
Since 0.6 is not an option, the correct answer is D: None of the above.