Which is CORRECT about information asymmetry and adverse selection

1. Information asymmetry refers to the situation when buyers have more information on the product than the sellers.
2. Information asymmetry is the result of adverse selection.
3. In a used car market, if sellers with good cars are unwilling to sell at a large discount, then only bad cars will get sold. This suboptimal outcome is so-called adverse selection.
4. Due to information asymmetry, market investors interpret firms SEO announcement positively because they believe insiders consider the firm undervalued.