A sell signal is indicated by a security's priceA) rising above the moving average. B) falling below the moving average. C) equaling the moving average. D) running parallel to the moving average.

Answer: Option B

Explanation: In simple words, sell signal refers to the indicators that gives an idea to the investor that the value of security is going to diminish in future and could cause loss to the investor.

If the security price is moving below the average of the market then it is an indicator that the other securities are performing better than the relative security. Hence that particular security's demand will be affected in future leading to further diminishing of the value.

Thus, from the above we can conclude that the correct option is B.