Which of the following is a the most accurate method of bedside confirmation of placement of a small bore naso gastric tube?

All of the following patients are at risk for alteration in nutrition except:

A. Patient L, whose weight is 10% above his ideal body weight.
B. Patient J, who is 86 years old, lives alone, and has poorly fitting dentures.
C. Patient M, a 17-year-old girl who weighs 90 pounds and frequently complains about her baby fat.
D. Patient K, who has been allowed nothing by mouth (NPO) for 7 days after bowel surgery and is receiving 3000 mL of 10% dextrose per day.