Answer:
a. December 1, 1999
Explanation:
A tombstone ad is an advertisement in the print form that can be appeared or advertised in a newspaper or a magazine. It is mostly used by any financial company or a firm where it is used publicly to share or express a transaction or a public offering of a stock of the company.
When any company registers a statement with the United States Securities and Exchange Commission for the public offering of a stock of the company, both 'tombstone ads' and 'red herring' can be expressed before the registration statement becomes effective.
In the question, SwissAire registration statement became effective on December 30, 1999.
Therefore the tombstone ad can be expressed before December 30, 1999 and after the registration and filing has been completed on December 1, 1999.
Therefore the answer is ---
a. December 1, 1999
