Unlike other research in language processing and speech production,

I thought like/unlike in comparisons can only be followed by a noun entity. In this case,
in the solution "Unlike other researchers who studied language processing and speech production", is this a noun entity because it's followed by a noun + 'noun + noun modifier'? I thought it was a clause as it has a subject+verb so I eliminated it.

Unlike other research in language processing and speech production, Broca was especially interested in the effects that damage to a particular brain area could have on speech.

(A) Unlike other research in language processing and speech production, Broca was especially interested in the effects that damage to a particular brain area could have on speech.
(B) Unlike language processing and speech production studied by other researchers,
(C) Unlike other researchers who studied language processing and speech production,
(D) In contrast to other researchers` studies of language processing and speech production,
(E) Although other researchers studied language processing and speech production,