Star stock picker Cathie Wood, head of ARK Invest, on Wednesday said she believed the U.S. stock market is not overvalued, and she talked up Tesla, her largest holding. “We are not in a bubble, that I know,” Wood said, speaking virtually at a Morningstar investment conference. “But I do believe the market is beginning to understand how profound some of these platform opportunities are, and how sustained and rapid the growth rates are going to be,” Wood said, referring to Tesla and other companies leveraging artificial intelligence and other emerging technologies. Fueled by massive fiscal and monetary stimulus, the S&P 500 is up almost 100 percent from its low in March 2020, near the start of the coronavirus pandemic. That has left the S&P 500 valued at about 21 times expected earnings, compared to an average forward PE of 16.5 over the past 10 years, according to Refinitiv data. …