Answer:
Option a: Draw down $10 million excess reserves and borrow $20 million from the Fed?
Step-by-step explanation:
I would choose option A because it is cheaper, since the Fed will always charge a lower rate than any bond issuance. Even if you compare it to the cost of issuing new stocks, the equity holders will also demand a higher return (higher cost of equity) than the Fed.
Option B is more expensive and will reduce the equity of current shareholders more.