There is no easy answer to this question, as there are many factors to consider when making an investment decision. Some important considerations include the stage of the startup (early vs. late stage), the sector or industry in which it operates, the company's competitive landscape, and the management team's experience and track record.
That said, there are a few well-known startups that have been successful in attracting large amounts of investment capital, such as Airbnb, Uber, and Pinterest. These companies have all achieved significant growth and have disrupted their respective industries.
If you're looking for a more detailed analysis of which startups are currently the most attractive to investors, this list from VentureScanner provides a good overview: https://www.venturescanner.com/blog/top-25-startups-to-watch-in-2018.