A security firm has been hired to perform an external penetration test against a company. The only information the firm received was the company name. Which of the following passive reconnaissance…

Deploying phishing emails is an active social engineering technique, not passive reconnaissance, and requires prior knowledge of target email addresses.

Running a vulnerability scan is an active assessment method that directly interacts with the target, thus not a passive reconnaissance approach.

Researching a company's vendor and supply chain (assuming 'Runtime' is a typo for 'Research/Review') is a highly effective passive reconnaissance technique that reveals critical third-party dependencies, technologies, and potential vulnerabilities within the broader attack surface, which can be more impactful than direct web scraping for initial external assessment.

While scraping web presences and social-networking sites is a valid passive reconnaissance technique, researching the vendor/supply chain can often provide more strategic insights into third-party dependencies and broader attack vectors for an external test, making it a potentially more 'positive' initial result.