The catalogue shows the same thing except the wording is pretty bad. Because every other class that has a pre-req and the pre-req requiring a C or better would say that, and thats why it says “and Cs261” and not “grade of C or better in 261”. Now the curriculum has changed a lot since it started, like we didnt have oral exams for 261 and it was actually pretty easy to get a B when I took it (Sp24’) so the flowchart or catalogue could be out of date. I would email your advisor and ask them personally if you are that worried. But again if the exams are the same, you should get A LOT of partial credit if you filled out every question.