36. Which is valid C expression?

1. 1. int $new_n = 20;

   
   
   

   2. int new n = 20;

   
   
   

   3. int n = 20;

   
   
   

   4. int new_n = 20;

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   Space, comma and $ cannot be used in a variable name.

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37. Which of the following is true for variable names in C?

1. 1. Variable can be of any length

   
   
   

   2. Variable names cannot start with a digit

   
   
   

   3. It is not an error to declare a variable to be one of the keywords(like goto, static)

   
   
   

   4. They can contain alphanumeric characters as well as special characters

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   According to the syntax for C variable name, it cannot start with a digit.

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38. Which of the following is not a valid C variable name?

1. 1. int $main;

   
   
   

   2. int var;

   
   
   

   3. float price;

   
   
   

   4. int num;

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   Since only underscore and no other special character is allowed in a variable name, it results in an error.

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39. C99 standard guarantees uniqueness of _____ characters for external names.

1. 1. 12

   
   
   

   2. 6

   
   
   

   3. 14

   
   
   

   4. 31

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   ISO C99 compiler may consider only first 31 characters for external names.

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40. Which of the following is not a valid variable name declaration?

1. 1. int __B11;

   
   
   

   2. int __11b;

   
   
   

   3. int __b11;

   
   
   

   4. All of above

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: E

   int a = 12; is a valid variable name declaration.

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