Which of the following statements concerning imperforate anus is true?

Imperforate anus affects males and females with equal frequency, occurring in 1 of each 20,000 live births. It is due to failure of descent of the urorectal septum. Imperforate anus may be broadly classified into "high" or "low," depending on whether the rectum ends above or below the level of the levator ani complex. In 90% of females, but only 50% of males, the lesion is of the low variety. The rectal fistula may end in the prostatic urethra or vagina in the high cases, while the low cases terminate in a perineal fistula. For the low cases, only a perineal operation may be required and these children will be expected to be continent. A pull-through procedure will be required for the high imperforate anus and the likelihood of continence is smaller. If there is doubt about the level or location of the termination of the rectum, it is better to perform a temporary colostomy than to compromise the ultimate chances of continence by an injudicious perineal approach.