Warren Harding 29th president of the United States is generally considered one of the least successful of the US presidents. Why?

He was an ineffectual leader who played poker while his friends plundered the U.S. treasury.Warren G. Harding's claim to infamy rests on spectacular ineptitude captured in his own pathetic words: "I am not fit for this office and should never have been here."

A former newspaperman and publisher who won a string of offices in his native Ohio, he was an unrestrained womanizer noted for his affability, good looks, and implacable desire to please. It was good, his father once told him, that he hadn't been born a girl, "because you'd be in the family way all the time. You can't say no."

Harding should have said no when Republican Party bosses in the proverbial smoke-filled room (a phrase that originated with this instance) made him their 11th-hour pick for the highest office. He was so reassuringly vague in his campaign declarations that he was understood to support both the foes and the backers of U.S. entry into the League of Nations, the hottest issue of the day.

i believe your answer is d)