How do you approach a question that asks for you to identify the conclusion from a few statements

As with all questions in the TSA, the focus on Speed as well as accuracy. First skim through the passage briefly to understand the nature of the argument. Next, if you've identfied the most important sentences consider these next to each other to see if one leads logically to the other (this is a nuanced skill and requires some practice). If you haven't identified the key sentences or are worried you've picked the wrong ones, try reading through the sentences individually starting with the last first to allow you to consider them out of context and narrow down your options.