I'd like to know the source of this problem as I have a few problems with it. With that said, here's my take on the question:
A. Unlike routine tests for diabetes or high cholesterol, typically costing less than $100, many newly discovered genetic defects require tests that are phenomenally expensive, with a “list price” close to $5000.
Comparing dissimilar things - Routine tests vs genetic defectsB. Unlike diabetes or high cholesterol, which typically require tests costing less than $100, the tests required for many newly discovered genetic defects are phenomenally expensive and have a “list price” close to $5000.
Same problem as above - this time comparing diabetes/high cholesterol with testsC. Unlike diabetes or high cholesterol, diseases that typically require tests costing less than $100, the tests required for many newly discovered genetic defects are phenomenally expensive and have a “list price” close to $5000.
Same problem as aboveD. Unlike routine tests for diabetes or high cholesterol, which typically cost less than $100, the tests required for many newly discovered genetic defects are phenomenally expensive, with a “list price” close to $5000.
This seems like the most logical/reasonable choice. The only iffy part about it is the which clause. We usually learn that which refers to the closest preceding noun, although in this case one can make the argument that the clause refers not to the closest noun (cholesterol) as is usually the case but rather "routine tests" as "cost" in the which clause signifies plurality.E. Unlike routine tests for diabetes or high cholesterol, diseases that typically cost less than $100, the tests required for many newly discovered genetic defects are phenomenally expensive, with a “list price” close to $5000.
Incorrectly attributes the $100 to the diseases rather than to the tests. If it was instead written "Unlike routine tests for diabetes or high cholesterol, tests that typically cost less than $100, the tests required for many newly discovered genetic defects are phenomenally expensive, with a “list price” close to $5000.", I would definitely have chosen E.I'd love to see the OA or even an OE if there is one. Also would love to have one of the frequent contributors or people who work at the various gmatprep companies chime in!