A perimenopausal woman presents with increasing swallowing difficulty and fatigue. Physical examination reveals that her thyroid is enlarged (palpable goiter). Laboratory examination of her serum reveals T4 of 4.9 mg/dL, free T4 of 2.5 ng/dL, and TSH of 5.5 mIU/mL. No thyroidstimulating immunoglobulins are identified in the serum, but antimicrosomal antibodies are present. Which one of the listed histologic findings, if present in a thyroid biopsy from this individual, would be most consistent with a diagnosis of Hashimoto's thyroiditis?
A
Lymphocytic infiltrate without follicle formation
B
Intense lymphoplasmacytic infiltrate with lymphoid follicles and scattered oxyphilic cells
C
Hyperplasia of follicular cells with scalloping of colloid at the margin of follicles
D
Granulomatous inflammation with multinucleated giant cells surrounding fragments of colloid