Answer:
a. hsp90 in the cytoplasm.
Step-by-step explanation:
Steroid receptors, such as the glucocorticoid receptor, are initially found in the cytoplasm of cells. Before they can be activated and translocated into the nucleus, steroid receptors are complexed with the cytoplasm's heat shock protein 90 (hsp90). This complex formation helps to maintain the receptor in an inactive state and prevents it from entering the nucleus prematurely.
Once the steroid hormone binds to the receptor in the cytoplasm, it triggers a series of events that lead to the dissociation of hsp90 from the receptor. This allows the activated steroid receptor to translocate into the nucleus, where it can bind to specific DNA sequences called hormone response elements (HREs) and regulate gene expression.
Therefore, the correct statement is that steroid receptors are complex with hsp90 in the cytoplasm.