Problem: An 82-year-old widow presents as an outpatient, with her son. She had experienced three falls in the previous year, none with any complaint of palpations or chest pain. She has a history of osteoarthritis which limits her mobility, hypertension, ischemic heart disease, urinary incontinence and anxiety. She has often been confused. She lives alone and is afraid to go out very much. She is taking aspirin, ramipril (an ACE inhibitor), furosemide (diuretic), verapamil (calcium channel blocker), escitalopram (antidepressant/antianxiety), ibuprofen (a non-steroidal anti-inflammatory drug), oxybutynin (antispasmodic for over-active bladder) and an over the counter cough syrup containing diphenhydramine. What is the next most appropriate step in the assessment of her falls? Group of answer choices Gait and balance assessment Holter monitoring Drug review Serum electrolyte measurement