Definitive diagnosis of multiple myeloma includes the triad of bone marrow plasmacytosis, lytic bone lesions, and:

Serum or urine components

Explanation:

Multiple myeloma is the cancer developed in the plasma cell that is a kind of white blood cell. The plasma cell helps in production of antibodies that protects the body from infection. Multiple myeloma causes the cancerous cells to aggregate in the bone marrow and covers the healthy cells.

The diagnosis of this type of cancer includes bone marrow biopsy, urine and blood tests. The bone marrow plasmocytosis includes the increase in plasma cells number in the bone marrow. The areas of bone damage that are due to cancerous plasma cell are the lytic bone lesions.

The proteins produced by the cancerous cells are detected in serum and urine samples. Thus, definitive diagnosis of multiple myeloma includes the triad of bone marrow plasmacytosis, lytic bone lesions, and Serum.

the correct answer is 2 and 4