Which Statement About Hormones and the Singing Behavior of Male

Which statement about hormones and the singing behavior of male birds is false?

A) Each spring, increases in circulating levels of testosterone cause areas of the brain that are related to learning song to increase in size.
B) Seasonal increases in the size of certain brain regions are due in part to increases in the size and branching patterns of individual neurons.
C) Research on bird song confirms that new neurons cannot be produced in the brains of adult vertebrates.
D) Hormones can change brain structure and brain function.
E) Singing behavior is induced in the spring when specific genes in the brain are triggered to be switched on.