47 Which of the following conclusions has been agreed upon by SL researchers?
(A) No scientific experiments have been conducted to study second language learning.
(B) It is hard for adult SL learners to excel in grammar and vocabulary.
(C) It is uncommon for adult SL learners to sound like native speakers.
(D) Success in adult second language learning should not be measured by how nativelike the SL learners can be.