Final answer:
Acquisition ads are specifically created to target new customers online, unlike email marketing and retargeting ads, which focus on engaging existing customers or previous website visitors.
Step-by-step explanation:
Among the options provided, d) Acquisition ads are primarily meant to target new customers online. Acquisition ads are specifically designed to reach individuals who have not previously interacted with the brand or product. Unlike email marketing, which relies on existing customer databases, and retargeting ads, which aim to re-engage individuals who have visited a website but did not complete a purchase, acquisition ads seek to expand the customer base by reaching new potential customers. Content marketing can attract new customers but is often broader, aiming to provide valuable information and establish brand expertise to attract, retain, and engage a clearly defined audience.