52.
Your Answer is
Correct Answer is J
Explanation
The first sentence of the option means the function of some bones of the woodpecker, and the meaning after the option is the two reasons for the woodpecker to drill holes. There is no obvious logical relationship between the preceding and following sentences, so there is no need for correlative words, J is correct.
F/G items: all are turning logical relationships.
Item H: even so "even so".