Final answer:
Unissued shares (option d) are shares that have never been sold by a company. They are part of a company's authorized shares.
Step-by-step explanation:
The correct option is d. unissued shares. Unissued shares are a type of shares that have never been sold by a company. These shares are part of a company's authorized shares, which represent the maximum number of shares that a company can issue.
While authorized shares are the total number of shares that a company can potentially issue, issued shares are the number of shares that have actually been issued and sold to investors. Outstanding shares, on the other hand, are the number of shares that have been issued and are currently held by shareholders.