Select the correct statements regarding Asynchronous Transfer Mode (ATM): a. ATM is a variable-length cell standard that supports voice, video and data b. ATM is connection-oriented c. ATM is a connectionless network layer protocol similar to IP, in which fixed cell sizes enable predicable latency and quality-of-service (QoS) d. a and b are correct statements

b. ATM is connection-oriented.

Explanation:

From the options given, option A is incorrect. The statement that ATM is a variable-length cell standard that supports voice, video and data is wrong. ATM isn't a variable length cell standard but rather it's a fixed length cell standard.

Option C is incorrect as well as ATM isn't a connectionless network layer protocol similar to IP but rather it is connection oriented which helps in offering predictability regarding latency. In such case, the users are offered quality-of-service.