The photograph below shows jamal’s bird feeder. jamal asked the question “are hummingbirds attracted to red feeders? ” then, he set up an experiment to test the question.

what is the independent variable in jamal’s experiment?
the amount of food

1. the amount of food

2.the color of the feeder

3.the height of the feeder

4.the number of hummingbirds

Option 2, The color of the feeder

Explanation:

In this experiment the researcher want to study whether the hummingbirds are attracted to red feeders. In this scenario all the features of red feeders which are able to grasp the attention of humming bird can be considered as independent variable. As an independent variable is the one which does not depend on any other factor but is responsible for the controlling the output of the research , the option 2 “the color of the feeder” seems to be the correct choice of answer as the rate/extent to which the humming bird is attracted towards the red feeder depend on the bright color of the feeder

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.