The shift from traditional dentistry to cosmetic dentistry i

[BTGmoderatorAT]

The shift from traditional dentistry to cosmetic dentistry is due to adults getting fewer cavities and becoming more conscious of their looks.

(A) dentistry to cosmetic dentistry is due to adults getting fewer cavities and becoming
(B) dentistry to cosmetic dentistry is happening because fewer adults are getting cavities and they are also becoming
(C) dentistry to cosmetic dentistry is because of adults who are getting both fewer cavities and becoming
(D) dentistry to cosmetic dentistry is taking place because adults are getting fewer cavities and are also becoming
(E) dentistry to cosmetic dentistry occurs because of adults getting fewer cavities and becomes

OA: D

What's wrong with options B and C? Can any experts help? Is

[elias.latour.apex]

What's wrong with (B)? Well, it contains the pronoun "they" yet it is unclear whether they refers to the people or to the cavities. In addition, the word "also" is repetitive and unnecessary. Generally speaking, it is not a good idea to combine and with also.

What's wrong with (C)? Several things. First of all, "because of" should not follow the word is. For example, we should say not "The traffic is because of the rain" but rather "The traffic is due to the rain." Second, choice (C) is not parallel. It uses the idiom both x and y., yet x and y do not go together. It says: Adults are getting BOTH A) fewer cavities AND B) becoming more conscious of their looks. While you can get "fewer cavities" you cannot get "becoming more conscious of their looks."