Research on C-testing has given us few accounts of the relationship between text characteristics and the nature of processing in the C-test completion. The present investigation set out to contribute to this line of research. The purpose of the study was two-fold: First, it attempted to explore the factors by which the difficulty of the C-test can be monitored; second, it intended to investigate whether difficult test tasks can trigger more macro-level processing in C-testing. In doing so, four texts with low and high degrees of syntactic complexity and abstraction were selected. These texts were then used to make two sets of C-test with the same content, but different formats: one with and the other without providing clues regarding the number of missing letters. 119 English-major BA students took the tests. Out of this sample, 36 students participated in the retrospective think-aloud phase of the study. The analyses revealed that employing texts with more syntactic complexity and abstraction, along with eliminating clues with respect to the number of missing letters can, in fact, result in more difficult test tasks which, in turn, seems to encourage more frequent use of macro-level processing on the part of the test takers. The findings can have implications for the text selection stage of various text-dependent reduced redundancy tests in general, and the C-test in particular. (Contains 8 tables.)