Correct Answer: B

Rationale: The correct answer is B. Clients taking digoxin should check their pulse before each dose to ensure it is within the appropriate range. Option A is incorrect because stopping the medication based solely on a heart rate below 80/min is not recommended. Option C is incorrect as having a pulse above 100/min doesn't necessarily indicate a need to stop digoxin. Option D is incorrect because digoxin should not be taken with an antacid as it can interfere with its absorption.

Correct Answer: A

Rationale: The correct answer is A: Potassium 3.5 mEq/L. Digoxin can cause hypokalemia as an adverse effect. Monitoring potassium levels is crucial because low potassium levels can increase the risk of digoxin toxicity. Choices B, C, and D are incorrect as they are not directly associated with potential adverse effects of digoxin. Sodium levels are not typically affected by digoxin, calcium levels are not a primary concern with digoxin therapy, and magnesium levels are not the most important to monitor for digoxin adverse effects.

Correct Answer: B

Rationale: Thrombophlebitis is a contraindication for the use of combination oral contraceptives due to the increased risk of thromboembolic events such as deep vein thrombosis and pulmonary embolism. Hyperthyroidism, diverticulosis, and hypocalcemia are not typically contraindications for using combination oral contraceptives, making choices A, C, and D incorrect.

Correct Answer: C

Rationale: Elevating the head of the bed reduces pressure on bony prominences, which helps prevent pressure ulcers.

Correct Answer: B

Rationale: The correct answer is to assist the client to the left Sims' position when administering an enema. This position helps facilitate the flow of the enema solution into the rectum. Placing the client in a high-Fowler's position (Choice A) is not ideal for administering an enema. Inserting the enema tubing 2.5 cm (1 in) into the rectum (Choice C) is incorrect as it should be inserted 7.5-10 cm (3-4 in) for an adult. Lubricating the tip of the enema tubing with petroleum jelly (Choice D) is a correct step to ease insertion but is not the most critical action among the choices provided.