A child wants a toy that is too big to be pulled straight through the bars of her crib. She studies the toy for some time and then grabs it, turns it sideways, and fits it through the bars. This child is using

Predisposing factors to sexual dysfunction include:

a) child-rearing factors b) sexual trauma c) anticipation of failure d) All of the above.

Efforts to find the gene or genes that underlie bipolar disorder suggest that

A) the underlying gene is on the X chromosome. B) the underlying gene is on the Y chromosome. C) there is a genetic basis for bipolar disorder, but not for cyclothymia. D) multiple genes are involved.