This question is incomplete because the options are missing; here is the missing section:
Which procedure should Juan use to test his hypothesis?
A. Survey northern and southern residents about the birds in their areas.
B. Observe the direction the birds fly when they depart in the winter.
C. Tag the hummingbirds with transmitters and track their movement.
D. Set up observation posts in the south to verify the time of year that birds arrive.
The answer to this question is C. Tag the hummingbirds with transmitters and track their movement.
Step-by-step explanation:
To prove or disprove his hypothesis about birds Juan needs to test the direction hummingbirds fly to during the winter because only in this way he can know if the birds fly to the South as he thinks or they go to a different place. Moreover, this can better be tested through precise instruments such as trackers because these will register the movement of birds and clearly show if they are going to the South. Moreover, others such as the opinions of residents or the initial direction when birds migrate might be inaccurate.