Which of the following four alternatives is not correct ? We need modulation :

Question:
Which of the following four alternatives is not correct? We need modulation :

to reduce the time lag between transmission and reception of the information signal
to reduce the size of antenna
to reduce the fractional band width, that is the ratio of the signal band width to the centre frequency
to increase the selectivity

Correct Option: 1

JEE Main Previous Year 1 Question of JEE Main from Physics Communication Systems chapter.

JEE Main Previous Year 2011 RS

Solution: