Which choice is closest in meaning to the phrase "never really caught on" in the last paragraph? 1. Was never taught in schools. 2. Was never fully developed. 3. Was never really popular. 4. Was never easy to learn.

Which choice is closest in meaning to the phrase "never really caught on" in the last paragraph? 1.  Was never taught in schools. 2.  Was never fully developed. 3.  Was never really popular. 4.  Was never easy to learn.