Answer:
A. HTTPS
Explanation:
Default HTTP port is 80. This means that the server request is received on port 80. But default HTTP request is susceptible to interception. In order to prevent it, HTTP communication is secured using SSL encryption (HTTPS protocol). In this case the Url string begins with 'https://' which differentiates it from normal web request. The default port used for HTTPS service is 443 instead of 80.