Correct Answer: B

Rationale: Tdap is recommended for preteens as part of the routine vaccination schedule to protect against these serious diseases.

Correct Answer: B

Rationale: In Guillain-Barre syndrome, decreased deep tendon reflexes are a critical finding that may indicate impending respiratory failure. This is due to the involvement of the peripheral nervous system affecting the muscles, including those involved in breathing. Reporting decreased deep tendon reflexes promptly is essential to prevent respiratory compromise. Facial weakness, difficulty speaking, and inability to move the eyes are common manifestations of Guillain-Barre syndrome but are not as immediately concerning as respiratory distress and impending respiratory failure.

Correct Answer: B

Rationale: Absence of breath sounds can indicate a pneumothorax or severe asthma exacerbation, which requires immediate intervention.

Correct Answer: C

Rationale: When the infant suckles at the breast, oxytocin is released by the posterior pituitary to stimulate the 'letdown' reflex and contract the uterus to prevent uterine hemorrhage.

Correct Answer: A

Rationale: A respiratory rate of 20 breaths per minute indicates effective oxygen therapy. In pneumonia, the respiratory rate typically increases due to the body's effort to improve oxygenation. Option B (pH of 7.35) is related to acid-base balance, not specifically indicating oxygen therapy effectiveness. Option C (oxygen saturation of 92%) is below the normal range (95-100%), suggesting the need for oxygen therapy. Option D (clear breath sounds) is a positive finding but not a direct indicator of oxygen therapy effectiveness.