To answer this question, we need to understand the syntax rules for JavaScript.
Option A) alert("hello "+3+" times); - This option has a syntax error. The closing parenthesis is missing at the end of the statement. The correct syntax should be alert("hello "+3+" times");.
Option B) alert("hello "+3 times); - This option also has a syntax error. The multiplication operator (*) is missing between the number 3 and the word "times". The correct syntax should be alert("hello "+3 * times); or alert("hello "+(3 * times)); depending on the value of the variable times.
Option C) alert("hello +3+ times"); - This option has no syntax error. It concatenates the string "hello ", the number 3, and the string " times" without any issues.
Option D) alert("hello "+3 +" times); - This option also has a syntax error. The closing parenthesis is missing at the end of the statement. The correct syntax should be alert("hello "+3 +" times");.
The correct answer is C. This option has no syntax error because it follows the correct syntax rules for concatenating strings and numbers in JavaScript.