Loading jQuery from the Google CDN: Simply put the following code on your functions.php file [Go to your WordPress Dashboard >> Appearenace >> Theme Editor >> Functions.php] & place it at the bottom, this should improve your score as well.

Please note this code may not work for all websites, depending on your theme. However, you can try it, if in case any feature does not work, simply remove the code.

Here are other tutorials to improve your GTmetrix Score:

• To improve Add Expire Headers & Leverage browser caching: Click here
• For Defer Parsing of JavaScript: Click  here
• Cache configuration as recommended by GTmetrix: Click here
• To serve Scaled Images & Optimize Images: Click here