Correct Answer: B

Rationale: Naegele's rule is a standard way of calculating an estimated delivery date (EDD). It involves subtracting three months from the first day of the last menstrual period (LMP), adding seven days, and then adding one year. In this case, subtracting three months from May 4th, 2013, gives February 4th. Adding seven days results in a due date of February 11th, 2014.

Correct Answer: A

Rationale: Cesarean birth doubles the risk for deep-vein thrombosis (DVT) due to immobility and vascular changes associated with surgery. Other risk factors include smoking, obesity, and a history of thromboembolism.

Correct Answer: C

Rationale: Vitamin B6 (pyridoxine) is often used to treat nausea and vomiting in pregnancy, including hyperemesis gravidarum, and is considered safe for use in pregnant clients.

Correct Answer: A

Rationale: An irregularly shaped, nontender lump is a concerning finding because it may indicate breast cancer. The nurse should report this finding to the provider for further investigation.

Correct Answer: C

Rationale: The correct course of action after missing oral contraceptive pills depends on how many pills are missed. If three pills are missed, the client should not 'double up' but rather follow the manufacturer's instructions and use an alternative form of contraception until the next cycle. Taking too many pills at once increases the risk of side effects without restoring contraceptive protection.