Which one of the following pituitary hormones do not have a particular target gland to act upon?

Somatotropin hormone is a peptide hormone. It is also called growth hormone. It is secreted by somatotrophic cells in the anterior pituitary. It stimulates the liver, cartilage, bones, and other tissues. Thyrotropin stimulates the thyroid gland, gonadotropins (FSH and LH) act on testis, ovary, and adrenocorticotropin acts on the adrenal cortex.