Alright. So here we have an example problem that wants us to complete the sentence using one of these five potential answer options down below. It says, for the insulin receptor to transduce the signal inside the cell, and option a says, the G α subunit needs to bind GTP to activate adenylate cyclase. Now of course, what we need to recall from our previous lesson videos is that the insulin receptor is an RTK or a receptor Tyrosine Kinase, and receptor Tyrosine Kinases are different receptor proteins than GPCRs, G protein-coupled receptors. And so recall that G α subunit is the subunit of a G protein, and G proteins are part of GPCR pathways, and they are not part of RTK pathways. And so what this means is that any of these answer options such as option a and b that include G α subunit is going to be incorrect because it's referring to the wrong type of pathway. Now, also, if we take a look at option d, it says that it needs to recruit a Tyrosine Kinase. And so by recruitment, what that means is it needs to essentially bring in a separate Tyrosine Kinase, but that is not what RTKs need to do. RTKs already have a covalently bound Tyrosine Kinase domain, and so, really, they don't need to recruit Tyrosine Kinases, for the most part. However, later in our course, we will talk about an exception to this. But here, the insulin receptor that we discussed in our last lesson video does not need to recruit a Tyrosine Kinase. It also mentions after dimerization, but again, we know that the insulin receptor is a unique RTK in the fact that it is actually already dimerized. And so there's really no dimerization step that is required since it forms these covalent disulfide bonds between its alpha beta subunits. We can eliminate option d for those reasons. And option e says it needs to recruit a Tyrosine Phosphatase to phosphorylate the cytoplasmic domain after dimerization. And so again, it's mentioning recruitment, so we know that it doesn't need to recruit that, but it also says Tyrosine Phosphatase. Recall, phosphatases do not phosphorylate things; instead, they do the opposite. They remove phosphate groups. And so for that reason, we know for sure this does not match up with the insulin receptor. And so, of course, this only leaves answer option c as the correct answer, and so for the insulin receptor to transduce the signal inside the cell, it needs to activate its Tyrosine Kinase domains via autophosphorylation after binding the insulin ligand. And so c here is the correct answer to this practice, and that concludes this practice or this example, and I'll see you guys in our next video.