4.In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation.
A、cool
B、flood
C、food
D、moon
29.
A、letting
B、hiding
C、having
D、allowing
Newspapers, magazines, televisions and computers all fight to____our attention.