Correct Answer  Option 4 : D
The correct answer is Terabyte.
 1 Bit = Binary Digit
 8 Bits = 1 Byte
 1024 Bytes = 1 Kilobyte
 1024 Kilobytes = 1 Megabyte
 1024 Megabytes = 1 Gigabyte
 1024 Gigabytes = 1 Terabyte
 1024 Terabytes = 1 Petabyte
 1024 Petabytes = 1 Exabyte
 1024 Exabytes = 1 Zettabyte
 1024 Zettabytes = 1 Yottabyte
 1024 Yottabytes = 1 Brontobyte
 1024 Brontobytes = 1 Geopbyte.
 A group of 4 bits is called a nibble.
 A group of 8 bits is called byte.
 A byte is the smallest unit, which can represent a data item or a character.

Bits are the basic building blocks of not only data storage but all computers.
 Computers work in binary digits, combining 0’s and 1’s in countless patterns.
 These binary digits are known as bits and are the smallest possible unit for data storage.
 When 8 bits are combined, you get a byte. Bytes are used to store a single character; whether’s it a letter, number, or punctuation.

All memory storage is expressed in terms of bytes, so although bits might be the foundation upon which data storage is built, bytes are the building blocks that truly denote the usability of any one storage solution.