If there are two or more words in variable we can use camel case to declare the variable. In camel case first character of first word is either a lowercase alphabet or underscore (_) and first character of second word is a uppercase alphabet. ex: empNum, myCar
So the Option (a) myCar is correct among the given options
Option (b) is incorrect
Since both the first letter of two words are in lower case which is not according to camel case rules
Option (c) is incorrect
The first letter of first word is in lower case first character of second word is auppercase alphabet but there is a gap so it is not valid .
Option (d) is incorrect
The first word is in upper case and first character of second word is auppercase alphabet it is not valid.
A or C are pretty much the same (as Linux is in the UNIX family). B depends on the version of Windows described. D is technically possible, but very difficult. The answer really comes down to cost (Linux is 'free' vs UNIX, which is licensed).
