Observing that traditional television puppets only can convey a limited range of expressions, Muppets creator Jim Henson began creating characters out of flexible foam rubber in order to allow them to express a wider array of emotions.
(A) only can convey a limited range of expressions,
(B) could convey only a limited range of expressions,
(C) conveying a limited range of expressions only,
(D) can only convey a limited expressive range,
(E) only could convey a limited expressive range,
Scroll down for the answer.
Modification, Idiomatic Usage
The easiest way to approach this question is to start by focusing on verb tense: the verb in the non-underlined portion is in the past tense (began), so logically, the beginning of the sentence must describe an action in the past as well. Can is in the present tense, so (A) and (D) can be eliminated. In addition, the underlined portion must contain a conjugated verb, so (C) can be crossed out as well.
Now you have two options: you can focus on either the placement of only or the idiomatic question of limited range of expressions vs. limited expressive range. If you choose to focus on the former, the key is to recognize that only is modifying limited range of expressions and so must be placed next to that phrase. Only (B) does so, making it the answer. Otherwise, if you can hear that the correct idiomatic phrase is range of expressions rather than expressive range, then you can identify (B) as the correct answer that way as well.