A 10-year-old boy complains of painful sore in the mouth, which has been persisting and increasing in size for 1,5 months. Objectively: on the buccal mucosa there is a soft shallow ulcer 2 cm in diameter with uneven undermined edges. The floor of the ulcer is tuberous, covered in yellowgray coating. The ulcer is surrounded with numerous yellowish tubercles. The regional lymph nodes are elastic, painful, and matted together. These symptoms are characteristic of the following disease: