Questions

The path that data takes from source to destination is called a Channel. A channel is a communication medium. A channel has a certain capacity for transmitting information. 

The "capacity" of a channel is the theoretical upper-limit to the bit rate over a given channel that will result in negligible errors. Channel capacity is often measured by its Bandwidth in Hz or its data rate in bits per second.

In a computer, the area where the data is stored for the quick access by the computer's processor is called Main storage or Primary storage or Memory or RAM.

Hence, main storage is also called Memory.

Digboi has the distinction of being India's oldest continuously producing oilfield. Digboi refinery, now a division of Indian Oil Corporation, had a capacity of about 0.65 MMTPA as of 2003. Digboi is now Headquarter of Assam Oil Division of Indian Oil Corporation Limited, though the crude production is not high today.

Here If you notice the difference, There is no question mark (?) at the end of the puzzle.

In that case, "What" is the name of the 5th child.