If we did a research study, I wonder how many times this question has been asked? I'd guess thousands. And, I bet they could all be answered by the person asking the question too.
Here's a start:
What is your budget?
What do you like that fits that budget?
Does the one that you like fit your requirements for durability, maintenance, usage?
If you have chosen a knife that you can answer affirmative to those last two questions, then there's your answer. Pretty simple. It's hard for anyone to tell another what knife is "best" because it may only be "best" for their requirements.