Refer to the Graph Showing the Locomotor Activity of Drosophila

Multiple Choice

Refer to the graph showing the locomotor activity of Drosophila melanogaster flies that have been subjected to various gene-knockout experiments. What can be inferred about the normal function of gene A in the graph?

A) Gene A plays little role in locomotor activity.
B) Gene A interacts with gene B in controlling locomotor activity.
C) Gene A interacts with gene C in controlling locomotor activity.
D) Gene A is required for locomotor activity.
E) There is insufficient data to make an inference.