Who has the most control over a corporation

The people who own shares in the corporation

Explanation:

"A corporation is owned by shareholders, who put their money together to help the company grow. The shareholders get a certain number of shares in the corporation for every dollar they put in. This is called "stock." Those who have the most shares have the most control over the corporation. These are usually the people who started the company and its top leaders. But sometimes a person with no other relationship to the corporation will buy up enough stock to take control of it."

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porter is writing economic history because he is focusing on the cost of developing vaccines.