Smallest individual unit in a program is called …………… .

Which of the following is not a token ?

1. keywords
2. identifiers
3. statement
4. operators

Identify the illegal identifier from the following.

1. _CHK
2. αβγτ
3. 20to50
4. AtoZ

Which of the following does not represent a character literal ?

1. 'a'
2. '1'
3. '\a'
4. "a"