I copied this solution from Gmatclub forum by Dolly Sharma. Thanks to you as I learnt something new I never heard before today due to the post.

Let's look at the structure here-

"the more coffee these doctors drank, more they had a likelihood of coronary disease

As the second part of the structure refers to 'likelihood', we need 'greater'. 'greater' is used when the noun is a number. For example: percentage, rate, likelihood, distance and population.

Also, 'likelihood' means 'the probability of a specified outcome'. Thus, it's imprecise to say they had a likelihood/probability of coronary disease. The correct usage should be "likelihood of having coronary disease'.

E goes out as it distorts the meaning. 'likelihood' was greater, NOT the disease.

This leaves us with D.

Now this is my analysis as someone who had no idea of likelihood specialty

we can eliminate A because of improper past perfect tense.
(C) the more coffee these doctors drank, the more they would have a likelihood to have coronary disease
first part is in past tense, the conditional + present perfect tense they would have a likelihood....... .correct me if I'm wrong
(E) greater was coronary disease likely...............terrible construction

left options
(B) more was their likelihood of having coronary disease
(D) greater was their likelihood of having coronary disease

Dolly's argument seems good. However I cant understand why we cant use more for greater? #DAVIDG@VERITASPREP or @Marty Murray help?

Thank you Mechmeera . Well , I did not know that likelihood is also a count noun.

now, the logic sounds perfect.

tricky for non native
we have idiom
likely to do something
but
likelihood of doing something, not likelihood to do something is correct idiom.

we are drawn to a wrong idiom.

if we focus on meaning, we can avoid the trap which attract us to grammar rules.

greater is better than more.

only d and e are left.

e is not clear.