There has been considerable research which investigates whether the underlying linguistic competence of L2 learners is constrained by principles and parameters of UG, parallel to the situation in L1 acquisition. In terms of the Scope Principle (henceforth SP), a principle of UG, which is associated with the scope interaction between a quantified expression and a wh-phrase, some experimental studies in EFL settings were conducted to investigate whether or not interlanguage grammars can be characterized by the principle. These experiments were carried out through the Truth Value Judgment Task (henceforth TVJT) alone, showing contrasting and confusing results, especially between Japanese learners and Korean learners. That is, while Japanese EFL learners observed the SP, Korean EFL learners did not despite the fact that both Japanese L1 grammar and Korean L1 grammar disallow the distributive interpretation, especially in the ambiguous sentence like what does everyone have? Therefore, the present study aims to confirm whether the same results are obtained provided that the identical experiment using the TVJT is repeated in other EFL learners. Noticeably, this study employed an additional, complementary task (Question and Answer Task, QAT) in addition to the TVJT as an attempt to increase the accuracy of the task and reflect learners’ actual knowledge of the target features. In QAT, the subjects were asked to write the answers to the target questions involving quantifiers and wh-questions in English. Results from the TVJT appeared, on the face of it, to provide support for the claim that the Korean EFL learners are under control of the Scope Principle. However, findings from QAT revealed that they are not constrained by the principle. Thus, it would be reasonable to conclude that the results of the present experiment do not fully support the claim that the Korean EFL learners’ interlanguage grammar has access to the UG-driven Scope Principle. Instead, it can be argued that Korean learners' interlanguage grammar may be affected by their L1 grammar, which gives rise to the claim that the explicit instruction on the interpretation of those sentences is required as part of overcoming this problem.