GMAT Sentence Correction (SC) | Re: Compared to high school students, who readily understand the

In option B, shouldnt 'Theorums of Gemetry' be followed by a relative pronoun such as 'that are' before introducing modifying phrase 'readily accesible to high school students'? Experts please resolve this confusion. Is this called Ellipsis? If yes then how to judge proper usage of Ellipsis?

Oreo

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