GMAT Sentence Correction (SC) | Re: Though margarine was introduced as a supposedly healthful

Though margarine was introduced as a supposedly healthful alternative to butter, recent studies suggest it is as
harmful or worse than butter.

• it is as harmful or worse than butter
• it is just as harmful or even worse than butter
• that it is as harmful as or worse than butter
• it is as harmful as if not worse than butter
• that it is as harmful if not worse than butter