Which of the following statements are true about the end-of-month stock prices from January to December?

Exhibit.

Which of the following statements are true about the end-of-month stock prices from January to December? Indicate all such statements.
A . From one month to the next, if the price of Stock X increased, then the price of Stock Y decreased.
B . From one month to the next, if the price of Stock Y remained the same, then the price of Stock X decreased.
C . From one month to the next, if the price of Stock Y decreased, then the price of Stock X increased.

Answer: A,C