Still others cite the difficulty of assembling a group of subjects whose depression is of comparable severity , increasing the chances that the effectiveness of the medication will be diffused .
Still others cite the difficulty of assembling a group of subjects whose depression is of comparable severity , a problem that complicates the task of properly measuring effectiveness .
(See options at the end). If the first sentence is true, is the second one also true?
Select from the following. a. no b. yes
b.