I . Phonetics(5 points)Directions:In each of the following groups of words, there are four underlined letters or lettercombinations marked A, B, C and D. Compare the underlined parts and identify theone that is different from the others in pronunciation. Mark your answer by blackeningthe corresponding letter on the Answer Sheet.1.
A、past
B、fast
C、grandson
D、reason
What do adolescent animals and human teenagers have in common?