The answer is A, or Locating bottlenecks in a network.
Explanation:
Refactoring consists of improving the internal structure of an existing program's source code, while preserving its external behavior.
Heart is attached to the lungs by the pulmonary artery and vein the artery carries deoxygenated blood to the pulmonary circuit (lungs) the lungs have a gas exchange and the deoxygenated blood goes back to the heart via the pulmonary vein.<span />
Linux. You do not need Linux as an operating system for your website.