Understanding Uninitialized Variables, Test case is wrong ? I guess?

Tell us what’s happening:
So basically I happened to have a problems on completing the test cases. And uses the test case data for a=6 b, and c as stated on test cases . But I don’t know why in this code right here works, I just use this line from the topic :

Initialize the three variables a , b , and c with 5 , 10 , and "I am a" respectively so that they will not be undefined .

Your code so far

// Only change code below this line
var a=5;
var b=10;
var c="I am a";
// Only change code above this line

a = a + 1;
b = b + 5;
c = c + " String!";

Challenge: Understanding Uninitialized Variables

Link to the challenge:

hello! your code looks fine, please check if a browser update is needed, I have seen that it can help with the tests

Thank you, I will consider updating if I encounter something like this again on my way thru this JavaScript Course.