According to a survey of graduating medical students conducted by Asso

According to a survey of graduating medical students conducted by Association of American Medical College, minority graduates are nearly four times more likely than are other graduates in planning to practice in socioeconomically deprived areas.

Option Elimination -

(A) minority graduates are nearly four times more likely than are other graduates in planning to practice -
"four times more likely" is wrong because, mathematically, it means five times. For example, assume the base probability is 10%. So four times more likely means = 10% + 4 (10%) = 50% = Five times.
"four times as likely" means = 4(10%) = 40% = Four times.

Moreover, "four times more" is redundant. E.g.,
The distance is three times longer. - ok
The distance is three times more longer - Incorrect because of redundancy.

His salary is double that of his colleague. - ok
His salary is double more than that of his colleague - incorrect.

"are" here may not be required.

The correct idiom is "likely to plan."

Both constructions are correct; it's mainly the author's preference
1. Likely to plan to practice
2. Likely to plan on practicing

E.g.,
He plans on learning Gen-AI and LLMs in the near future. ok
He plans to learn Gen-AI and LLMs in the near future. - ok.

(B) minority graduates are nearly four times more likely than other graduates who plan on practicing - "four times more likely than" is wrong. Moreover, the comparison is broken by the relative clause "who plan on practicing..."

(C) minority graduates are nearly four times as likely as other graduates to plan on practicing - "four times as likely as" is correct and implies "four times." "To plan" is the right idiom. Either "on practicing" or "to practice" is correct. It's purely the author's personal preference.

(D) it is nearly four times more likely that minority graduates rather than other graduates will plan to practice - "ING" modifier with "According to...." modifies "it"? "four times more" is redundant and not preferred usage. "more ..rather than" is wrong. The usage of "rather than" is itself wrong. When we say "X rather than Y," we share a preference between X and Y. Here, there is no preference between "minority graduates" and "other graduates." "likely will plan" is wrong. "likely" conveys probability, and "will" conveys certainty - a bit contradictory to use. It has to be "likely to plan."

(E) it is nearly four times as likely for minority graduates than other graduates to plan to practice - "it" issues. "as ..than" wrong.