Question

The site of proteolysis of tri iodothyronin & tetraiodothyronin
(1) E.R.
(2) Golgi body
(3) Lysosome
(4) in thyroid follicle

Answer 1

The precursor of the hormones, iodinated thyroglobulin, is endocytosed in vesicles, which fuse with the lysosomes of the follicular cell. There, thyroglobulin is cleaved and the hormones are released into the lumen of the vesicle which is ultimately exocytosed.
Therefore, the answer 3 is correct