Option 1 refers to Arbitrage, not Beta, where an asset is bought and sold simultaneously on different platforms to take advantage of differing prices for the same asset.

Option 2 can be an aspect of beta but it isn`t completely accurate because beta itself doesn`t define an investment strategy but rather helps in deciding one. It is a tool used by portfolio managers for this but isn`t an investment strategy itself.

Option 3 discusses a specific type of risk, but beta is a general measure of risk relating to the responsiveness of a stock`s price changes to the overall market changes. It does not specify systemic risk where perfect hedging isn`t possible.

Option 4 is the correct answer. Beta is indeed a numeric value that measures the tendency of a stock`s price to respond to swings in the overall market. A beta higher than 1 suggests that the stock`s price would be more volatile than the market, while a beta less than 1 indicates less volatility.