What is the Best Title for an Investment Stage Between Seed and Series A with Early Traction and Institutional Investors?

Investment stage. If the investment sweet spot you’d like to focus on is: i) already some early stage institutional investor in the cap table (i.e. don’t be the first) ii) some early traction but not yet proven market fit (i.e. scale-up but pre-round A). How would you suggest to define this in the context of the investment thesis: A) Seed B) Pre Series A C) Seed plus or Seed Extension or Late Sees D) Series A. Any feedback and explanation highly welcome! Tx!