Answer:
The correct answer is - a week.
Explanation:
The transdermal or Ortho Evra contraceptive patch is of birth control that is considered simple and safe. This patch can be wear on the upper arm, butt, belly skin and other skin, it releases hormones that prevent pregnancy.
This patch must be wear for full one week or 7 days before changing to new for three weeks. Like other birth control pills, it also contains estrogen hormone and progestin which is absorbed by the skin and inhibits ovulation.
Thus, the correct answer is - a week.