Final answer:
When you buy 300 shares of a company, you have purchased a round lot.
Step-by-step explanation:
When you buy 300 shares of a company, you have purchased a round lot.
In the stock market, a round lot refers to a standard trading unit, usually consisting of 100 shares. It is the most common way individuals buy and sell stocks. An odd lot, on the other hand, refers to a trading unit that is less than a standard round lot, such as buying or selling 50 shares.
Therefore, the correct answer is A) A round lot.