Alrighty. So this one asks us, generally speaking, renal autoregulation maintains glomerular filtration rate directly, whereas external factors regulate glomerular filtration rate indirectly. Let's run through the answers and see what we have. So a is directly for renal autoregulation and then indirectly for external factors and it looks like we got it in one. That is the correct answer.
So remember, renal autoregulation is our kidneys monitoring glomerular filtration rate and making any changes as needed to directly affect it, whereas external factors are factors that impact systemic blood pressure. And then because of that, they naturally affect glomerular filtration rate indirectly. So our answer is a. That is the reason b would be incorrect. C, we obviously do not have any conscious control over our glomerular filtration rate.
So c is out. And then d, slowly and quickly. We need all of these to work pretty quickly. And if anything, the renal autoregulation will be a little bit quicker since that's directly impacting the glomerular filtration rate. So d would be out as well, and that is why our answer is a.
