which of the responses is (are) correct. Biochemical investigations to monitor AX include?

1    C-reactive protein

2    erythrocyte sedimentation rate

3    rheumatoid factor

A    if 1, 2 and 3 are correct

B    if 1 and 2 only are correct

C    if 2 and 3 only are correct

D    if 1 only is correct

E    if 3 only is correct