It’s worse than that. The survey is not accurate, as it is out of date. The actual percentage who can answer correctly is actually much, much lower.
The correct response is the Legislative, the Judicial-legislative, and the Execu-legislative.
Anyone paying attention knows this (apparently a very small number of people, which is why it has become this way).
Right you are.
Even among those who can name the actual branches envisioned by the founders, very, very few know that the branches were not supposed to be equal. The legislative was to be preeminent, followed by the executive, with the judicial intended to be weakest.